231561432 has 24 divisors (see below), whose sum is σ = 627145740. Its totient is φ = 77187120.

The previous prime is 231561431. The next prime is 231561439. The reversal of 231561432 is 234165132.

231561432 is a `hidden beast` number, since 2 + 3 + 15 + 614 + 32 = 666.

It is a tau number, because it is divible by the number of its divisors (24).

It is a junction number, because it is equal to n+sod(n) for n = 231561396 and 231561405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231561431) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1607994 + ... + 1608137.

Almost surely, 2^231561432 is an apocalyptic number.

It is an amenable number.

231561432 is an abundant number, since it is smaller than the sum of its proper divisors (395584308).

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

231561432 is a wasteful number, since it uses less digits than its factorization.

231561432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3216143 (or 3216136 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 231561432 is about 15217.1427015718. The cubic root of 231561432 is about 614.0759312914.

The spelling of 231561432 in words is "two hundred thirty-one million, five hundred sixty-one thousand, four hundred thirty-two".