816720972 has 12 divisors (see below), whose sum is σ = 1905682296. Its totient is φ = 272240320.

The previous prime is 816720959. The next prime is 816720991. The reversal of 816720972 is 279027618.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×816720972² = 1334066292209249568, which contains 22 as substring.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 34030029 + ... + 34030052.

It is an arithmetic number, because the mean of its divisors is an integer number (158806858).

Almost surely, 2^816720972 is an apocalyptic number.

It is an amenable number.

816720972 is an abundant number, since it is smaller than the sum of its proper divisors (1088961324).

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

816720972 is a wasteful number, since it uses less digits than its factorization.

816720972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68060088 (or 68060086 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 42.

The square root of 816720972 is about 28578.3304620826. The cubic root of 816720972 is about 934.7408785605.

The spelling of 816720972 in words is "eight hundred sixteen million, seven hundred twenty thousand, nine hundred seventy-two".