811572 has 12 divisors (see below), whose sum is σ = 1893696. Its totient is φ = 270520.

The previous prime is 811561. The next prime is 811583. The reversal of 811572 is 275118.

It is an interprime number because it is at equal distance from previous prime (811561) and next prime (811583).

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

It is a super-2 number, since 2×811572² = 1317298222368, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

811572 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33804 + ... + 33827.

It is an arithmetic number, because the mean of its divisors is an integer number (157808).

2⁸¹¹⁵⁷² is an apocalyptic number.

It is an amenable number.

811572 is an abundant number, since it is smaller than the sum of its proper divisors (1082124).

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

811572 is a wasteful number, since it uses less digits than its factorization.

811572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67638 (or 67636 counting only the distinct ones).

The product of its digits is 560, while the sum is 24.

The square root of 811572 is about 900.8729100156. The cubic root of 811572 is about 93.2772395367.

It can be divided in two parts, 81 and 1572, that added together give a triangular number (1653 = T₅₇).

The spelling of 811572 in words is "eight hundred eleven thousand, five hundred seventy-two".