123590891 has 4 divisors (see below), whose sum is σ = 128964432. Its totient is φ = 118217352.

The previous prime is 123590879. The next prime is 123590921. The reversal of 123590891 is 198095321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 198095321 = 1069 ⋅185309.

It is a cyclic number.

It is not a de Polignac number, because 123590891 - 2⁶ = 123590827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123590491) 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, 2686736 + ... + 2686781.

It is an arithmetic number, because the mean of its divisors is an integer number (32241108).

Almost surely, 2^123590891 is an apocalyptic number.

123590891 is a deficient number, since it is larger than the sum of its proper divisors (5373541).

123590891 is an equidigital number, since it uses as much as digits as its factorization.

123590891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5373540.

The product of its (nonzero) digits is 19440, while the sum is 38.

The square root of 123590891 is about 11117.1440127400. The cubic root of 123590891 is about 498.1140835820.

The spelling of 123590891 in words is "one hundred twenty-three million, five hundred ninety thousand, eight hundred ninety-one".