231371640 has 80 divisors (see below), whose sum is σ = 777676680. Its totient is φ = 61698240.

The previous prime is 231371629. The next prime is 231371663. The reversal of 231371640 is 46173132.

231371640 is a `hidden beast` number, since 2 + 3 + 13 + 7 + 1 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 32466 + ... + 38945.

Almost surely, 2^231371640 is an apocalyptic number.

231371640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231371640 is an abundant number, since it is smaller than the sum of its proper divisors (546305040).

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

231371640 is a wasteful number, since it uses less digits than its factorization.

231371640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71434 (or 71421 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 231371640 is about 15210.9052985021. The cubic root of 231371640 is about 613.9081161333.

The spelling of 231371640 in words is "two hundred thirty-one million, three hundred seventy-one thousand, six hundred forty".