71631372031 has 4 divisors (see below), whose sum is σ = 71634553200. Its totient is φ = 71628190864.

The previous prime is 71631371993. The next prime is 71631372079. The reversal of 71631372031 is 13027313617.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 71631372031 - 2³³ = 63041437439 is a prime.

It is a super-2 number, since 2×71631372031² (a number of 23 digits) 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 (71631376031) 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, 1556566 + ... + 1601923.

It is an arithmetic number, because the mean of its divisors is an integer number (17908638300).

Almost surely, 2^71631372031 is an apocalyptic number.

71631372031 is a deficient number, since it is larger than the sum of its proper divisors (3181169).

71631372031 is a wasteful number, since it uses less digits than its factorization.

71631372031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3181168.

The product of its (nonzero) digits is 15876, while the sum is 34.

Adding to 71631372031 its reverse (13027313617), we get a palindrome (84658685648).

The spelling of 71631372031 in words is "seventy-one billion, six hundred thirty-one million, three hundred seventy-two thousand, thirty-one".