Pi is both an irrational number and a transcendental number.
To any set that contains it! It belongs to {-15}, or {sqrt(2), -15, pi, -3/7}, or all whole numbers between -43 and 53, or multiples of 5, or composite numbers, or integers, or rational numbers, or real numbers, or complex numbers, etc.
To any set that contains it! It belongs to {-22}, or {-22, sqrt(2), pi, -3/7}, or all whole numbers between -43 and 53, or multiples of 11, or composite numbers, or integers, or rational numbers, or real numbers, etc.
Real, complex, quaternion, etc. But more specifically it's a transcendental real number, not being the root of an integer polynomial (and certainly not the ratio of two integers).
To any set that contains it! It belongs to {0}, or {45, 0, sqrt(2), pi, -3/7}, or {0, bananas, France, cold} or all whole numbers between -43 and 53, or multiples of 5, or integers, or rational numbers, or real numbers, or complex numbers, etc.
Pi is both an irrational number and a transcendental number.
To any set that contains it! It belongs to {sqrt(30)}, or {45, sqrt(30), pi, -3/7}, or irrational numbers, or real numbers between -6 and 6, or all real numbers or complex numbers, etc.
It belongs to the interval (25, 27.3), or [-20.9, 10*pi], and infinitely more such intervals.It also belongs to the set of rational numbers, real numbers, complex numbers and quaternions.
To any set that contains it! It belongs to {-15}, or {sqrt(2), -15, pi, -3/7}, or all whole numbers between -43 and 53, or multiples of 5, or composite numbers, or integers, or rational numbers, or real numbers, or complex numbers, etc.
Pi belongs to the sets of real numbers, transcendental numbers and irrational numbers.
If you're talking about real numbers, then it is an irrational number. Any number that cannot be written as a fraction is irrational. You cannot write pi as a fraction (22/7 is just an estimate). So any thing multiplied with pi cannot be rational either.
To any set that contains it! It belongs to {14}, or {14, sqrt(2), pi, -3/7}, or all whole numbers between 3 and 53, or multiples of 7, or composite numbers, or counting numbers, or integers, or rational numbers, or real numbers, etc.
To any set that contains it! It belongs to {-22}, or {-22, sqrt(2), pi, -3/7}, or all whole numbers between -43 and 53, or multiples of 11, or composite numbers, or integers, or rational numbers, or real numbers, etc.
Real, complex, quaternion, etc. But more specifically it's a transcendental real number, not being the root of an integer polynomial (and certainly not the ratio of two integers).
Any subset which will have it! It is in {17}or {-3, pi, 17, sqrt(37/6)}or {45, bananas, France, cold}or all whole numbers between -43 and 53, or multiples of 17, or prime numbers, or counting numbers, or integers, or rational numbers, or real numbers.
To any set that contains it! It belongs to {5.385164807}, or {45, sqrt(2), pi, 5.385164807, -3/7}, or all numbers between 4 and 53, or rational numbers, or real numbers, or complex numbers, etc.
To any set that contains it! It belongs to {-5}, or {45, sqrt(2), -5, pi, -3/7}, or all whole numbers between -43 and 53, or multiples of 5, or integers, or rational numbers, or real numbers, etc.