86311921 has 2 divisors, whose sum is σ = 86311922. Its totient is φ = 86311920.

The previous prime is 86311919. The next prime is 86311943. The reversal of 86311921 is 12911368.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68973025 + 17338896 = 8305^2 + 4164^2 .

It is a cyclic number.

It is not a de Polignac number, because 86311921 - 2¹ = 86311919 is a prime.

Together with 86311919, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (86311961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43155960 + 43155961.

It is an arithmetic number, because the mean of its divisors is an integer number (43155961).

Almost surely, 2^86311921 is an apocalyptic number.

It is an amenable number.

86311921 is a deficient number, since it is larger than the sum of its proper divisors (1).

86311921 is an equidigital number, since it uses as much as digits as its factorization.

86311921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 31.

The square root of 86311921 is about 9290.4209269548. The cubic root of 86311921 is about 441.9335038476.

The spelling of 86311921 in words is "eighty-six million, three hundred eleven thousand, nine hundred twenty-one".