231644643 has 4 divisors (see below), whose sum is σ = 308859528. Its totient is φ = 154429760.

The previous prime is 231644591. The next prime is 231644659. The reversal of 231644643 is 346446132.

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 231644643 - 2¹² = 231640547 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231644683) 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, 38607438 + ... + 38607443.

It is an arithmetic number, because the mean of its divisors is an integer number (77214882).

Almost surely, 2^231644643 is an apocalyptic number.

231644643 is a deficient number, since it is larger than the sum of its proper divisors (77214885).

231644643 is an equidigital number, since it uses as much as digits as its factorization.

231644643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77214884.

The product of its digits is 41472, while the sum is 33.

The square root of 231644643 is about 15219.8765763721. The cubic root of 231644643 is about 614.1494780136.

The spelling of 231644643 in words is "two hundred thirty-one million, six hundred forty-four thousand, six hundred forty-three".