90211057 has 4 divisors (see below), whose sum is σ = 90236916. Its totient is φ = 90185200.

The previous prime is 90211049. The next prime is 90211073. The reversal of 90211057 is 75011209.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 62078641 + 28132416 = 7879^2 + 5304^2 .

It is a cyclic number.

It is not a de Polignac number, because 90211057 - 2³ = 90211049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90211087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6694 + ... + 15007.

It is an arithmetic number, because the mean of its divisors is an integer number (22559229).

Almost surely, 2^90211057 is an apocalyptic number.

It is an amenable number.

90211057 is a deficient number, since it is larger than the sum of its proper divisors (25859).

90211057 is a wasteful number, since it uses less digits than its factorization.

90211057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25858.

The product of its (nonzero) digits is 630, while the sum is 25.

The square root of 90211057 is about 9497.9501472686. The cubic root of 90211057 is about 448.4905092682.

The spelling of 90211057 in words is "ninety million, two hundred eleven thousand, fifty-seven".