31123138 has 8 divisors (see below), whose sum is σ = 47098188. Its totient is φ = 15423744.

The previous prime is 31123123. The next prime is 31123139. The reversal of 31123138 is 83132113.

It can be written as a sum of positive squares in 2 ways, for example, as 23299929 + 7823209 = 4827^2 + 2797^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (31123139) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68631 + ... + 69082.

Almost surely, 2^31123138 is an apocalyptic number.

31123138 is a deficient number, since it is larger than the sum of its proper divisors (15975050).

31123138 is a wasteful number, since it uses less digits than its factorization.

31123138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137828.

The product of its digits is 432, while the sum is 22.

The square root of 31123138 is about 5578.8115221793. The cubic root of 31123138 is about 314.5534547865.

The spelling of 31123138 in words is "thirty-one million, one hundred twenty-three thousand, one hundred thirty-eight".