65231891 has 2 divisors, whose sum is σ = 65231892. Its totient is φ = 65231890.

The previous prime is 65231879. The next prime is 65231909. The reversal of 65231891 is 19813256.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65231891 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (65231191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32615945 + 32615946.

It is an arithmetic number, because the mean of its divisors is an integer number (32615946).

Almost surely, 2^65231891 is an apocalyptic number.

65231891 is a deficient number, since it is larger than the sum of its proper divisors (1).

65231891 is an equidigital number, since it uses as much as digits as its factorization.

65231891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 35.

The square root of 65231891 is about 8076.6262139584. The cubic root of 65231891 is about 402.5501469097.

The spelling of 65231891 in words is "sixty-five million, two hundred thirty-one thousand, eight hundred ninety-one".