31995880 has 64 divisors (see below), whose sum is σ = 82800000. Its totient is φ = 10900224.

The previous prime is 31995871. The next prime is 31995881. The reversal of 31995880 is 8859913.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31995881) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 63871 + ... + 64369.

It is an arithmetic number, because the mean of its divisors is an integer number (1293750).

Almost surely, 2^31995880 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 31995880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41400000).

31995880 is an abundant number, since it is smaller than the sum of its proper divisors (50804120).

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

31995880 is a wasteful number, since it uses less digits than its factorization.

31995880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 746 (or 742 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 43.

The square root of 31995880 is about 5656.4900777779. The cubic root of 31995880 is about 317.4665846165.

The spelling of 31995880 in words is "thirty-one million, nine hundred ninety-five thousand, eight hundred eighty".