231491643 has 4 divisors (see below), whose sum is σ = 308655528. Its totient is φ = 154327760.

The previous prime is 231491639. The next prime is 231491677. The reversal of 231491643 is 346194132.

231491643 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 231491643 - 2² = 231491639 is a prime.

It is not an unprimeable number, because it can be changed into a prime (231491683) 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, 38581938 + ... + 38581943.

It is an arithmetic number, because the mean of its divisors is an integer number (77163882).

Almost surely, 2^231491643 is an apocalyptic number.

231491643 is a deficient number, since it is larger than the sum of its proper divisors (77163885).

231491643 is an equidigital number, since it uses as much as digits as its factorization.

231491643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77163884.

The product of its digits is 15552, while the sum is 33.

The square root of 231491643 is about 15214.8494241645. The cubic root of 231491643 is about 614.0142341270.

The spelling of 231491643 in words is "two hundred thirty-one million, four hundred ninety-one thousand, six hundred forty-three".