156
16 if the prime factors don't have to be distinct. 210 if they do.
Not two DISTINCT prime factors, no. For example, 64 = 2^6 only has prime factor 2. All even numbers which are not a power of 2 must have at least two distinct prime factors, however; one of them will, of course, be 2.
All odd numbers with one or two distinct prime factors are deficient. Since 3 and 7 are factors of 63, it must be deficient.
All the prime factors of 76 are 2 and 19.
They are the products of two distinct prime numbers. Along with one and the numbers themselves, they all total four factors.
If p, q and r are distinct primes and n=pxqxr then n will have 8 factors, all of which will be positive since prime numbers are all positive, which are: n(pqr), pq, pr, qr, p, q, r and 1. Here there were 3 distinct primes so the number of positive factors is 2^3. In general if you had p distinct primes then you would have 2^p positive factors.
16 if the prime factors don't have to be distinct. 210 if they do.
Not two DISTINCT prime factors, no. For example, 64 = 2^6 only has prime factor 2. All even numbers which are not a power of 2 must have at least two distinct prime factors, however; one of them will, of course, be 2.
Yes, 12 has prime factors. The prime factors of 12 are 2, 2, and 3, so the distinct prime factors are 2 and 3. Almost all integers have prime factors. The integers without prime factors are -1, 0, and 1.
All numbers (except for 1 and 0) have prime factors. Sometimes the prime factors are repeated. The prime factorization of 216 is 2 x 2 x 2 x 3 x 3 x 3. The distinct prime factors of 216 are 2 and 3.
They are divisible only by themselves and one.
1 and 59. It is a prime number.
30, 42, 66, 78, 102, 105, 114, 138 all have exactly three distinct prime factors.
The only number between 30 and 40 with distinct prime factors which add up to 12 is 35.
The only distinct prime factor that 3125 has is 5.
All odd numbers with one or two distinct prime factors are deficient. Since 3 and 7 are factors of 63, it must be deficient.
Distinct would mean they are all different, so take the 3 lowest primes and multiply them: 2*3*5 = 30