90185657 has 2 divisors, whose sum is σ = 90185658. Its totient is φ = 90185656.

The previous prime is 90185617. The next prime is 90185659. The reversal of 90185657 is 75658109.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88755241 + 1430416 = 9421^2 + 1196^2 .

It is a cyclic number.

It is not a de Polignac number, because 90185657 - 2¹⁴ = 90169273 is a prime.

Together with 90185659, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (90185659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45092828 + 45092829.

It is an arithmetic number, because the mean of its divisors is an integer number (45092829).

Almost surely, 2^90185657 is an apocalyptic number.

It is an amenable number.

90185657 is a deficient number, since it is larger than the sum of its proper divisors (1).

90185657 is an equidigital number, since it uses as much as digits as its factorization.

90185657 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 75600, while the sum is 41.

The square root of 90185657 is about 9496.6129225108. The cubic root of 90185657 is about 448.4484126981.

The spelling of 90185657 in words is "ninety million, one hundred eighty-five thousand, six hundred fifty-seven".