90554021 has 2 divisors, whose sum is σ = 90554022. Its totient is φ = 90554020.

The previous prime is 90554017. The next prime is 90554033. The reversal of 90554021 is 12045509.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49773025 + 40780996 = 7055^2 + 6386^2 .

It is a cyclic number.

It is not a de Polignac number, because 90554021 - 2² = 90554017 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90554521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45277010 + 45277011.

It is an arithmetic number, because the mean of its divisors is an integer number (45277011).

Almost surely, 2^90554021 is an apocalyptic number.

It is an amenable number.

90554021 is a deficient number, since it is larger than the sum of its proper divisors (1).

90554021 is an equidigital number, since it uses as much as digits as its factorization.

90554021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 90554021 is about 9515.9876523669. The cubic root of 90554021 is about 449.0581469429.

The spelling of 90554021 in words is "ninety million, five hundred fifty-four thousand, twenty-one".