90565091 has 2 divisors, whose sum is σ = 90565092. Its totient is φ = 90565090.

The previous prime is 90565081. The next prime is 90565109. The reversal of 90565091 is 19056509.

Together with next prime (90565109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 90565091 - 2²⁶ = 23456227 is a prime.

It is a Chen prime.

It is equal to p_5247962 and since 90565091 and 5247962 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (90565021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45282545 + 45282546.

It is an arithmetic number, because the mean of its divisors is an integer number (45282546).

Almost surely, 2^90565091 is an apocalyptic number.

90565091 is a deficient number, since it is larger than the sum of its proper divisors (1).

90565091 is an equidigital number, since it uses as much as digits as its factorization.

90565091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12150, while the sum is 35.

The square root of 90565091 is about 9516.5692873010. The cubic root of 90565091 is about 449.0764449381.

The spelling of 90565091 in words is "ninety million, five hundred sixty-five thousand, ninety-one".