72564138 has 24 divisors (see below), whose sum is σ = 157579968. Its totient is φ = 24133032.

The previous prime is 72564133. The next prime is 72564169. The reversal of 72564138 is 83146527.

72564138 is a `hidden beast` number, since 7 + 2 + 5 + 641 + 3 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (72564131) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3981 + ... + 12687.

It is an arithmetic number, because the mean of its divisors is an integer number (6565832).

Almost surely, 2^72564138 is an apocalyptic number.

72564138 is an abundant number, since it is smaller than the sum of its proper divisors (85015830).

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

72564138 is a wasteful number, since it uses less digits than its factorization.

72564138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9178 (or 9175 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 72564138 is about 8518.4586633968. The cubic root of 72564138 is about 417.1004709343.

The spelling of 72564138 in words is "seventy-two million, five hundred sixty-four thousand, one hundred thirty-eight".