31138212 has 24 divisors (see below), whose sum is σ = 83035456. Its totient is φ = 8896608.

The previous prime is 31138193. The next prime is 31138213. The reversal of 31138212 is 21283113.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31138213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 185263 + ... + 185430.

Almost surely, 2^31138212 is an apocalyptic number.

It is an amenable number.

31138212 is an abundant number, since it is smaller than the sum of its proper divisors (51897244).

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

31138212 is a wasteful number, since it uses less digits than its factorization.

31138212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 370707 (or 370705 counting only the distinct ones).

The product of its digits is 288, while the sum is 21.

The square root of 31138212 is about 5580.1623632292. The cubic root of 31138212 is about 314.6042295882.

It can be divided in two parts, 3113 and 8212, that added together give a triangular number (11325 = T₁₅₀).

The spelling of 31138212 in words is "thirty-one million, one hundred thirty-eight thousand, two hundred twelve".