79971631 has 4 divisors (see below), whose sum is σ = 81098064. Its totient is φ = 78845200.

The previous prime is 79971629. The next prime is 79971637. The reversal of 79971631 is 13617997.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13617997 = 107 ⋅127271.

It is a cyclic number.

It is not a de Polignac number, because 79971631 - 2¹ = 79971629 is a prime.

It is a super-2 number, since 2×79971631² = 12790923529600322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79971637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 563110 + ... + 563251.

It is an arithmetic number, because the mean of its divisors is an integer number (20274516).

Almost surely, 2^79971631 is an apocalyptic number.

79971631 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

79971631 is a deficient number, since it is larger than the sum of its proper divisors (1126433).

79971631 is a wasteful number, since it uses less digits than its factorization.

79971631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1126432.

The product of its digits is 71442, while the sum is 43.

The square root of 79971631 is about 8942.6858940701. The cubic root of 79971631 is about 430.8359993533.

The spelling of 79971631 in words is "seventy-nine million, nine hundred seventy-one thousand, six hundred thirty-one".