31655628840 has 128 divisors (see below), whose sum is σ = 104416542720. Its totient is φ = 7613625600.

The previous prime is 31655628761. The next prime is 31655628841. The reversal of 31655628840 is 4882655613.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 31655628840.

It is not an unprimeable number, because it can be changed into a prime (31655628841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 73225 + ... + 262055.

It is an arithmetic number, because the mean of its divisors is an integer number (815754240).

Almost surely, 2^31655628840 is an apocalyptic number.

31655628840 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31655628840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52208271360).

31655628840 is an abundant number, since it is smaller than the sum of its proper divisors (72760913880).

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

31655628840 is a wasteful number, since it uses less digits than its factorization.

31655628840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188983 (or 188979 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 48.

The spelling of 31655628840 in words is "thirty-one billion, six hundred fifty-five million, six hundred twenty-eight thousand, eight hundred forty".