72172508 has 12 divisors (see below), whose sum is σ = 126463680. Its totient is φ = 36040032.

The previous prime is 72172493. The next prime is 72172519. The reversal of 72172508 is 80527127.

It is a super-2 number, since 2×72172508² = 10417741822020128, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7916 + ... + 14387.

It is an arithmetic number, because the mean of its divisors is an integer number (10538640).

Almost surely, 2^72172508 is an apocalyptic number.

It is an amenable number.

72172508 is a deficient number, since it is larger than the sum of its proper divisors (54291172).

72172508 is a wasteful number, since it uses less digits than its factorization.

72172508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23116 (or 23114 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 32.

The square root of 72172508 is about 8495.4404241334. The cubic root of 72172508 is about 416.3487506300.

The spelling of 72172508 in words is "seventy-two million, one hundred seventy-two thousand, five hundred eight".