81474631 has 8 divisors (see below), whose sum is σ = 93187584. Its totient is φ = 69780120.

The previous prime is 81474623. The next prime is 81474647. The reversal of 81474631 is 13647418.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81474631 - 2³ = 81474623 is a prime.

It is a super-2 number, since 2×81474631² = 13276230993172322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81474031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6726 + ... + 14428.

It is an arithmetic number, because the mean of its divisors is an integer number (11648448).

Almost surely, 2^81474631 is an apocalyptic number.

81474631 is a deficient number, since it is larger than the sum of its proper divisors (11712953).

81474631 is a wasteful number, since it uses less digits than its factorization.

81474631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9221.

The product of its digits is 16128, while the sum is 34.

The square root of 81474631 is about 9026.3298743177. The cubic root of 81474631 is about 433.5183323829.

The spelling of 81474631 in words is "eighty-one million, four hundred seventy-four thousand, six hundred thirty-one".