72168904 has 8 divisors (see below), whose sum is σ = 135316710. Its totient is φ = 36084448.

The previous prime is 72168869. The next prime is 72168913. The reversal of 72168904 is 40986127.

It can be written as a sum of positive squares in only one way, i.e., 72080100 + 88804 = 8490^2 + 298^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×72168904² = 10416701409122432, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4510549 + ... + 4510564.

Almost surely, 2^72168904 is an apocalyptic number.

It is an amenable number.

72168904 is a deficient number, since it is larger than the sum of its proper divisors (63147806).

72168904 is a wasteful number, since it uses less digits than its factorization.

72168904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9021119 (or 9021115 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 72168904 is about 8495.2283077031. The cubic root of 72168904 is about 416.3418202631.

The spelling of 72168904 in words is "seventy-two million, one hundred sixty-eight thousand, nine hundred four".