72155988 has 24 divisors (see below), whose sum is σ = 187071360. Its totient is φ = 24051960.

The previous prime is 72155971. The next prime is 72156011. The reversal of 72155988 is 88955127.

It is a happy number.

It is a super-2 number, since 2×72155988² = 10412973208512288, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 333948 + ... + 334163.

It is an arithmetic number, because the mean of its divisors is an integer number (7794640).

Almost surely, 2^72155988 is an apocalyptic number.

It is an amenable number.

72155988 is an abundant number, since it is smaller than the sum of its proper divisors (114915372).

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

72155988 is a wasteful number, since it uses less digits than its factorization.

72155988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 668124 (or 668116 counting only the distinct ones).

The product of its digits is 201600, while the sum is 45.

The square root of 72155988 is about 8494.4680822286. The cubic root of 72155988 is about 416.3169813483.

It can be divided in two parts, 7215 and 5988, that added together give a triangular number (13203 = T₁₆₂).

The spelling of 72155988 in words is "seventy-two million, one hundred fifty-five thousand, nine hundred eighty-eight".