72162891 has 24 divisors (see below), whose sum is σ = 110017440. Its totient is φ = 45488256.

The previous prime is 72162889. The next prime is 72162899. The reversal of 72162891 is 19826127.

72162891 is a `hidden beast` number, since 7 + 21 + 628 + 9 + 1 = 666.

It is not a de Polignac number, because 72162891 - 2¹ = 72162889 is a prime.

Its product of digits (12096) is a multiple of the sum of its prime divisors (4032).

It is not an unprimeable number, because it can be changed into a prime (72162899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16465 + ... + 20381.

It is an arithmetic number, because the mean of its divisors is an integer number (4584060).

Almost surely, 2^72162891 is an apocalyptic number.

72162891 is a deficient number, since it is larger than the sum of its proper divisors (37854549).

72162891 is a wasteful number, since it uses less digits than its factorization.

72162891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4035 (or 4032 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 72162891 is about 8494.8743957754. The cubic root of 72162891 is about 416.3302569593.

The spelling of 72162891 in words is "seventy-two million, one hundred sixty-two thousand, eight hundred ninety-one".