90809893 has 2 divisors, whose sum is σ = 90809894. Its totient is φ = 90809892.

The previous prime is 90809891. The next prime is 90809941. The reversal of 90809893 is 39890809.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59259204 + 31550689 = 7698^2 + 5617^2 .

It is a cyclic number.

It is not a de Polignac number, because 90809893 - 2¹ = 90809891 is a prime.

Together with 90809891, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90809891) 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, 45404946 + 45404947.

It is an arithmetic number, because the mean of its divisors is an integer number (45404947).

Almost surely, 2^90809893 is an apocalyptic number.

It is an amenable number.

90809893 is a deficient number, since it is larger than the sum of its proper divisors (1).

90809893 is an equidigital number, since it uses as much as digits as its factorization.

90809893 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 139968, while the sum is 46.

The square root of 90809893 is about 9529.4224903716. The cubic root of 90809893 is about 449.4807063227.

The spelling of 90809893 in words is "ninety million, eight hundred nine thousand, eight hundred ninety-three".