216318972 has 24 divisors (see below), whose sum is σ = 509744592. Its totient is φ = 71392000.

The previous prime is 216318967. The next prime is 216318997. The reversal of 216318972 is 279813612.

It is a self number, because there is not a number n which added to its sum of digits gives 216318972.

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, 88029 + ... + 90452.

It is an arithmetic number, because the mean of its divisors is an integer number (21239358).

Almost surely, 2^216318972 is an apocalyptic number.

It is an amenable number.

216318972 is an abundant number, since it is smaller than the sum of its proper divisors (293425620).

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

216318972 is a wasteful number, since it uses less digits than its factorization.

216318972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178589 (or 178587 counting only the distinct ones).

The product of its digits is 36288, while the sum is 39.

The square root of 216318972 is about 14707.7861012458. The cubic root of 216318972 is about 600.2951991830.

It can be divided in two parts, 21631 and 8972, that added together give a palindrome (30603).

The spelling of 216318972 in words is "two hundred sixteen million, three hundred eighteen thousand, nine hundred seventy-two".