90205637 has 2 divisors, whose sum is σ = 90205638. Its totient is φ = 90205636.

The previous prime is 90205543. The next prime is 90205639. The reversal of 90205637 is 73650209.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 89094721 + 1110916 = 9439^2 + 1054^2 .

It is a cyclic number.

It is not a de Polignac number, because 90205637 - 2¹⁶ = 90140101 is a prime.

Together with 90205639, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90205639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45102818 + 45102819.

It is an arithmetic number, because the mean of its divisors is an integer number (45102819).

Almost surely, 2^90205637 is an apocalyptic number.

It is an amenable number.

90205637 is a deficient number, since it is larger than the sum of its proper divisors (1).

90205637 is an equidigital number, since it uses as much as digits as its factorization.

90205637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11340, while the sum is 32.

The square root of 90205637 is about 9497.6648182593. The cubic root of 90205637 is about 448.4815271200.

The spelling of 90205637 in words is "ninety million, two hundred five thousand, six hundred thirty-seven".