72129892 has 6 divisors (see below), whose sum is σ = 126227318. Its totient is φ = 36064944.

The previous prime is 72129859. The next prime is 72129899. The reversal of 72129892 is 29892127.

It can be written as a sum of positive squares in only one way, i.e., 64256256 + 7873636 = 8016^2 + 2806^2 .

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (72129899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9016233 + ... + 9016240.

Almost surely, 2^72129892 is an apocalyptic number.

It is an amenable number.

72129892 is a deficient number, since it is larger than the sum of its proper divisors (54097426).

72129892 is a wasteful number, since it uses less digits than its factorization.

72129892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18032477 (or 18032475 counting only the distinct ones).

The product of its digits is 36288, while the sum is 40.

The square root of 72129892 is about 8492.9318848087. The cubic root of 72129892 is about 416.2667867711.

The spelling of 72129892 in words is "seventy-two million, one hundred twenty-nine thousand, eight hundred ninety-two".