90086221 has 2 divisors, whose sum is σ = 90086222. Its totient is φ = 90086220.

The previous prime is 90086219. The next prime is 90086251. The reversal of 90086221 is 12268009.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72488196 + 17598025 = 8514^2 + 4195^2 .

It is a cyclic number.

It is not a de Polignac number, because 90086221 - 2¹ = 90086219 is a prime.

Together with 90086219, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 90086221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90086251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45043110 + 45043111.

It is an arithmetic number, because the mean of its divisors is an integer number (45043111).

Almost surely, 2^90086221 is an apocalyptic number.

It is an amenable number.

90086221 is a deficient number, since it is larger than the sum of its proper divisors (1).

90086221 is an equidigital number, since it uses as much as digits as its factorization.

90086221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 90086221 is about 9491.3761383690. The cubic root of 90086221 is about 448.2835368317.

The spelling of 90086221 in words is "ninety million, eighty-six thousand, two hundred twenty-one".