31106920 has 64 divisors (see below), whose sum is σ = 76043520. Its totient is φ = 11384064.

The previous prime is 31106917. The next prime is 31106921. The reversal of 31106920 is 2960113.

It is a junction number, because it is equal to n+sod(n) for n = 31106891 and 31106900.

It is not an unprimeable number, because it can be changed into a prime (31106921) 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, 84577 + ... + 84943.

It is an arithmetic number, because the mean of its divisors is an integer number (1188180).

Almost surely, 2^31106920 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 31106920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38021760).

31106920 is an abundant number, since it is smaller than the sum of its proper divisors (44936600).

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

31106920 is a wasteful number, since it uses less digits than its factorization.

31106920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 554 (or 550 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 31106920 is about 5577.3577973804. The cubic root of 31106920 is about 314.4988082585.

The spelling of 31106920 in words is "thirty-one million, one hundred six thousand, nine hundred twenty".