31089906 has 96 divisors (see below), whose sum is σ = 76422528. Its totient is φ = 9434880.

The previous prime is 31089899. The next prime is 31089911. The reversal of 31089906 is 60998013.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 437851 + ... + 437921.

It is an arithmetic number, because the mean of its divisors is an integer number (796068).

Almost surely, 2^31089906 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31089906, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38211264).

31089906 is an abundant number, since it is smaller than the sum of its proper divisors (45332622).

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

31089906 is a wasteful number, since it uses less digits than its factorization.

31089906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158 (or 146 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 31089906 is about 5575.8323145518. The cubic root of 31089906 is about 314.4414591909.

The spelling of 31089906 in words is "thirty-one million, eighty-nine thousand, nine hundred six".