72533538 has 96 divisors (see below), whose sum is σ = 199480320. Its totient is φ = 18499680.

The previous prime is 72533497. The next prime is 72533557. The reversal of 72533538 is 83533527.

72533538 is a `hidden beast` number, since 72 + 53 + 3 + 538 = 666.

It is a super-2 number, since 2×72533538² = 10522228269594888, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 81331 + ... + 82217.

It is an arithmetic number, because the mean of its divisors is an integer number (2077920).

Almost surely, 2^72533538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72533538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99740160).

72533538 is an abundant number, since it is smaller than the sum of its proper divisors (126946782).

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

72533538 is a wasteful number, since it uses less digits than its factorization.

72533538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 972 (or 969 counting only the distinct ones).

The product of its digits is 75600, while the sum is 36.

The square root of 72533538 is about 8516.6623744281. The cubic root of 72533538 is about 417.0418328372.

The spelling of 72533538 in words is "seventy-two million, five hundred thirty-three thousand, five hundred thirty-eight".