91360021 has 2 divisors, whose sum is σ = 91360022. Its totient is φ = 91360020.

The previous prime is 91360019. The next prime is 91360051. The reversal of 91360021 is 12006319.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 86229796 + 5130225 = 9286^2 + 2265^2 .

It is a cyclic number.

It is not a de Polignac number, because 91360021 - 2¹ = 91360019 is a prime.

Together with 91360019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 91359974 and 91360001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91360001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45680010 + 45680011.

It is an arithmetic number, because the mean of its divisors is an integer number (45680011).

Almost surely, 2^91360021 is an apocalyptic number.

It is an amenable number.

91360021 is a deficient number, since it is larger than the sum of its proper divisors (1).

91360021 is an equidigital number, since it uses as much as digits as its factorization.

91360021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 91360021 is about 9558.2436148071. The cubic root of 91360021 is about 450.3865337301.

The spelling of 91360021 in words is "ninety-one million, three hundred sixty thousand, twenty-one".