31621655616 has 224 divisors, whose sum is σ = 92311971840. Its totient is φ = 9508663296.

The previous prime is 31621655591. The next prime is 31621655719. The reversal of 31621655616 is 61655612613.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22066036 + ... + 22067468.

Almost surely, 2^31621655616 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31621655616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46155985920).

31621655616 is an abundant number, since it is smaller than the sum of its proper divisors (60690316224).

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

31621655616 is a wasteful number, since it uses less digits than its factorization.

31621655616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1753 (or 1743 counting only the distinct ones).

The product of its digits is 194400, while the sum is 42.

The spelling of 31621655616 in words is "thirty-one billion, six hundred twenty-one million, six hundred fifty-five thousand, six hundred sixteen".