231561865 has 8 divisors (see below), whose sum is σ = 278016768. Its totient is φ = 185154480.

The previous prime is 231561857. The next prime is 231561871. The reversal of 231561865 is 568165132.

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

It is not a de Polignac number, because 231561865 - 2³ = 231561857 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91 + ... + 21520.

It is an arithmetic number, because the mean of its divisors is an integer number (34752096).

Almost surely, 2^231561865 is an apocalyptic number.

It is an amenable number.

231561865 is a deficient number, since it is larger than the sum of its proper divisors (46454903).

231561865 is a wasteful number, since it uses less digits than its factorization.

231561865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23759.

The product of its digits is 43200, while the sum is 37.

The square root of 231561865 is about 15217.1569289404. The cubic root of 231561865 is about 614.0763140476.

The spelling of 231561865 in words is "two hundred thirty-one million, five hundred sixty-one thousand, eight hundred sixty-five".