31685647680 has 84 divisors (see below), whose sum is σ = 108985435572. Its totient is φ = 8449505280.

The previous prime is 31685647633. The next prime is 31685647729. The reversal of 31685647680 is 8674658613.

31685647680 is a `hidden beast` number, since 3 + 1 + 6 + 8 + 564 + 76 + 8 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 18309337344 + 13376310336 = 135312^2 + 115656^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5498101 + ... + 5503860.

Almost surely, 2^31685647680 is an apocalyptic number.

31685647680 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31685647680 is an abundant number, since it is smaller than the sum of its proper divisors (77299787892).

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

31685647680 is a wasteful number, since it uses less digits than its factorization.

31685647680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11001984 (or 11001971 counting only the distinct ones).

The product of its (nonzero) digits is 5806080, while the sum is 54.

The spelling of 31685647680 in words is "thirty-one billion, six hundred eighty-five million, six hundred forty-seven thousand, six hundred eighty".