72857128 has 16 divisors (see below), whose sum is σ = 137592000. Its totient is φ = 36165936.

The previous prime is 72857051. The next prime is 72857131. The reversal of 72857128 is 82175827.

It is a super-2 number, since 2×72857128² = 10616322200816768, which contains 22 as substring.

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, 31648 + ... + 33871.

It is an arithmetic number, because the mean of its divisors is an integer number (8599500).

Almost surely, 2^72857128 is an apocalyptic number.

It is an amenable number.

72857128 is a deficient number, since it is larger than the sum of its proper divisors (64734872).

72857128 is a wasteful number, since it uses less digits than its factorization.

72857128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65664 (or 65660 counting only the distinct ones).

The product of its digits is 62720, while the sum is 40.

The square root of 72857128 is about 8535.6386990078. The cubic root of 72857128 is about 417.6610883510.

The spelling of 72857128 in words is "seventy-two million, eight hundred fifty-seven thousand, one hundred twenty-eight".