31130906 has 4 divisors (see below), whose sum is σ = 46696362. Its totient is φ = 15565452.

The previous prime is 31130903. The next prime is 31130929. The reversal of 31130906 is 60903113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60903113 = 19 ⋅3205427.

It can be written as a sum of positive squares in only one way, i.e., 26615281 + 4515625 = 5159^2 + 2125^2 .

It is not an unprimeable number, because it can be changed into a prime (31130903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7782725 + ... + 7782728.

Almost surely, 2^31130906 is an apocalyptic number.

31130906 is a deficient number, since it is larger than the sum of its proper divisors (15565456).

31130906 is a wasteful number, since it uses less digits than its factorization.

31130906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15565455.

The product of its (nonzero) digits is 486, while the sum is 23.

The square root of 31130906 is about 5579.5076843750. The cubic root of 31130906 is about 314.5796223276.

The spelling of 31130906 in words is "thirty-one million, one hundred thirty thousand, nine hundred six".