231766561 has 16 divisors (see below), whose sum is σ = 261080064. Its totient is φ = 204139584.

The previous prime is 231766553. The next prime is 231766609. The reversal of 231766561 is 165667132.

It is a cyclic number.

It is not a de Polignac number, because 231766561 - 2³ = 231766553 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 231766561.

It is not an unprimeable number, because it can be changed into a prime (231766061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 180855 + ... + 182131.

It is an arithmetic number, because the mean of its divisors is an integer number (16317504).

Almost surely, 2^231766561 is an apocalyptic number.

It is an amenable number.

231766561 is a deficient number, since it is larger than the sum of its proper divisors (29313503).

231766561 is a wasteful number, since it uses less digits than its factorization.

231766561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1920.

The product of its digits is 45360, while the sum is 37.

The square root of 231766561 is about 15223.8812725271. The cubic root of 231766561 is about 614.2572044328.

The spelling of 231766561 in words is "two hundred thirty-one million, seven hundred sixty-six thousand, five hundred sixty-one".