72557136 has 30 divisors (see below), whose sum is σ = 203059610. Its totient is φ = 24185664.

The previous prime is 72557129. The next prime is 72557141. The reversal of 72557136 is 63175527.

72557136 is a `hidden beast` number, since 72 + 557 + 1 + 36 = 666.

It can be written as a sum of positive squares in only one way, i.e., 53582400 + 18974736 = 7320^2 + 4356^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 72557136.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 251791 + ... + 252078.

Almost surely, 2^72557136 is an apocalyptic number.

It is an amenable number.

72557136 is an abundant number, since it is smaller than the sum of its proper divisors (130502474).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72557136 is a wasteful number, since it uses less digits than its factorization.

72557136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503883 (or 503874 counting only the distinct ones).

The product of its digits is 44100, while the sum is 36.

The square root of 72557136 is about 8518.0476636375. The cubic root of 72557136 is about 417.0870546127.

The spelling of 72557136 in words is "seventy-two million, five hundred fifty-seven thousand, one hundred thirty-six".