231981565 has 16 divisors (see below), whose sum is σ = 291600000. Its totient is φ = 176832832.

The previous prime is 231981553. The next prime is 231981571. The reversal of 231981565 is 565189132.

It is not a de Polignac number, because 231981565 - 2¹⁹ = 231457277 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27186 + ... + 34684.

It is an arithmetic number, because the mean of its divisors is an integer number (18225000).

Almost surely, 2^231981565 is an apocalyptic number.

It is an amenable number.

231981565 is a deficient number, since it is larger than the sum of its proper divisors (59618435).

231981565 is a wasteful number, since it uses less digits than its factorization.

231981565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7796.

The product of its digits is 64800, while the sum is 40.

The square root of 231981565 is about 15230.9410411832. The cubic root of 231981565 is about 614.4470893725.

The spelling of 231981565 in words is "two hundred thirty-one million, nine hundred eighty-one thousand, five hundred sixty-five".