99565891 has 2 divisors, whose sum is σ = 99565892. Its totient is φ = 99565890.

The previous prime is 99565883. The next prime is 99565897. The reversal of 99565891 is 19856599.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 99565891 - 2³ = 99565883 is a prime.

It is not a weakly prime, because it can be changed into another prime (99565897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49782945 + 49782946.

It is an arithmetic number, because the mean of its divisors is an integer number (49782946).

Almost surely, 2^99565891 is an apocalyptic number.

99565891 is a deficient number, since it is larger than the sum of its proper divisors (1).

99565891 is an equidigital number, since it uses as much as digits as its factorization.

99565891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 874800, while the sum is 52.

The square root of 99565891 is about 9978.2709424028. The cubic root of 99565891 is about 463.4862572812.

The spelling of 99565891 in words is "ninety-nine million, five hundred sixty-five thousand, eight hundred ninety-one".