90239221 has 2 divisors, whose sum is σ = 90239222. Its totient is φ = 90239220.

The previous prime is 90239209. The next prime is 90239239. The reversal of 90239221 is 12293209.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89984196 + 255025 = 9486^2 + 505^2 .

It is a cyclic number.

It is not a de Polignac number, because 90239221 - 2¹⁵ = 90206453 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 90239221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90239321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45119610 + 45119611.

It is an arithmetic number, because the mean of its divisors is an integer number (45119611).

Almost surely, 2^90239221 is an apocalyptic number.

90239221 is the 5485-th hex number.

It is an amenable number.

90239221 is a deficient number, since it is larger than the sum of its proper divisors (1).

90239221 is an equidigital number, since it uses as much as digits as its factorization.

90239221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 90239221 is about 9499.4326672702. The cubic root of 90239221 is about 448.5371775032.

The spelling of 90239221 in words is "ninety million, two hundred thirty-nine thousand, two hundred twenty-one".