72756864 has 96 divisors (see below), whose sum is σ = 211351140. Its totient is φ = 24023040.

The previous prime is 72756857. The next prime is 72756869. The reversal of 72756864 is 46865727.

72756864 is a `hidden beast` number, since 7 + 27 + 568 + 64 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 72590400 + 166464 = 8520^2 + 408^2 .

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×72756864² = 10587122518228992, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (72756869) 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, 157594 + ... + 158054.

Almost surely, 2^72756864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72756864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105675570).

72756864 is an abundant number, since it is smaller than the sum of its proper divisors (138594276).

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

72756864 is a wasteful number, since it uses less digits than its factorization.

72756864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 618 (or 603 counting only the distinct ones).

The product of its digits is 564480, while the sum is 45.

The square root of 72756864 is about 8529.7634199314. The cubic root of 72756864 is about 417.4694091155.

The spelling of 72756864 in words is "seventy-two million, seven hundred fifty-six thousand, eight hundred sixty-four".