31978147860 has 72 divisors (see below), whose sum is σ = 98329194600. Its totient is φ = 8410687488.

The previous prime is 31978147841. The next prime is 31978147871. The reversal of 31978147860 is 6874187913.

31978147860 is a `hidden beast` number, since 3 + 1 + 97 + 81 + 478 + 6 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 14663272464 + 17314875396 = 121092^2 + 131586^2 .

It is a junction number, because it is equal to n+sod(n) for n = 31978147797 and 31978147806.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1203685 + ... + 1229964.

Almost surely, 2^31978147860 is an apocalyptic number.

31978147860 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31978147860 is an abundant number, since it is smaller than the sum of its proper divisors (66351046740).

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

31978147860 is a wasteful number, since it uses less digits than its factorization.

31978147860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2433737 (or 2433732 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The spelling of 31978147860 in words is "thirty-one billion, nine hundred seventy-eight million, one hundred forty-seven thousand, eight hundred sixty".