31978499231 has 8 divisors (see below), whose sum is σ = 37534609440. Its totient is φ = 26669327328.

The previous prime is 31978499219. The next prime is 31978499239. The reversal of 31978499231 is 13299487913.

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

It is not a de Polignac number, because 31978499231 - 2³⁰ = 30904757407 is a prime.

It is a super-2 number, since 2×31978499231² (a number of 22 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 (31978499239) 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, 61734296 + ... + 61734813.

It is an arithmetic number, because the mean of its divisors is an integer number (4691826180).

Almost surely, 2^31978499231 is an apocalyptic number.

31978499231 is a deficient number, since it is larger than the sum of its proper divisors (5556110209).

31978499231 is a wasteful number, since it uses less digits than its factorization.

31978499231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123469153.

The product of its digits is 2939328, while the sum is 56.

The spelling of 31978499231 in words is "thirty-one billion, nine hundred seventy-eight million, four hundred ninety-nine thousand, two hundred thirty-one".