31102172 has 6 divisors (see below), whose sum is σ = 54428808. Its totient is φ = 15551084.

The previous prime is 31102157. The next prime is 31102199. The reversal of 31102172 is 27120113.

It is a self number, because there is not a number n which added to its sum of digits gives 31102172.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3887768 + ... + 3887775.

It is an arithmetic number, because the mean of its divisors is an integer number (9071468).

Almost surely, 2^31102172 is an apocalyptic number.

It is an amenable number.

31102172 is a deficient number, since it is larger than the sum of its proper divisors (23326636).

31102172 is a wasteful number, since it uses less digits than its factorization.

31102172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7775547 (or 7775545 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 31102172 is about 5576.9321315576. The cubic root of 31102172 is about 314.4828062851.

Adding to 31102172 its reverse (27120113), we get a palindrome (58222285).

The spelling of 31102172 in words is "thirty-one million, one hundred two thousand, one hundred seventy-two".