231990138 has 24 divisors (see below), whose sum is σ = 506608128. Its totient is φ = 76720392.

The previous prime is 231990119. The next prime is 231990151. The reversal of 231990138 is 831099132.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 48456 + ... + 53027.

It is an arithmetic number, because the mean of its divisors is an integer number (21108672).

Almost surely, 2^231990138 is an apocalyptic number.

231990138 is an abundant number, since it is smaller than the sum of its proper divisors (274617990).

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

231990138 is a wasteful number, since it uses less digits than its factorization.

231990138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101618 (or 101615 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 231990138 is about 15231.2224722771. Note that the first 3 decimals coincide. The cubic root of 231990138 is about 614.4546583504.

The spelling of 231990138 in words is "two hundred thirty-one million, nine hundred ninety thousand, one hundred thirty-eight".