231377891 has 2 divisors, whose sum is σ = 231377892. Its totient is φ = 231377890.

The previous prime is 231377873. The next prime is 231377899. The reversal of 231377891 is 198773132.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 231377891 - 2⁶ = 231377827 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (231377899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115688945 + 115688946.

It is an arithmetic number, because the mean of its divisors is an integer number (115688946).

Almost surely, 2^231377891 is an apocalyptic number.

231377891 is a deficient number, since it is larger than the sum of its proper divisors (1).

231377891 is an equidigital number, since it uses as much as digits as its factorization.

231377891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 63504, while the sum is 41.

The square root of 231377891 is about 15211.1107746936. The cubic root of 231377891 is about 613.9136447641.

The spelling of 231377891 in words is "two hundred thirty-one million, three hundred seventy-seven thousand, eight hundred ninety-one".