231561051 has 4 divisors (see below), whose sum is σ = 308748072. Its totient is φ = 154374032.

The previous prime is 231561013. The next prime is 231561101. The reversal of 231561051 is 150165132.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 231561051 - 2¹⁰ = 231560027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231561251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38593506 + ... + 38593511.

It is an arithmetic number, because the mean of its divisors is an integer number (77187018).

Almost surely, 2^231561051 is an apocalyptic number.

231561051 is a deficient number, since it is larger than the sum of its proper divisors (77187021).

231561051 is an equidigital number, since it uses as much as digits as its factorization.

231561051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77187020.

The product of its (nonzero) digits is 900, while the sum is 24.

The square root of 231561051 is about 15217.1301827907. The cubic root of 231561051 is about 614.0755945009.

The spelling of 231561051 in words is "two hundred thirty-one million, five hundred sixty-one thousand, fifty-one".