90864121 has 2 divisors, whose sum is σ = 90864122. Its totient is φ = 90864120.

The previous prime is 90864073. The next prime is 90864139. The reversal of 90864121 is 12146809.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63824121 + 27040000 = 7989^2 + 5200^2 .

It is a cyclic number.

It is not a de Polignac number, because 90864121 - 2²⁵ = 57309689 is a prime.

It is not a weakly prime, because it can be changed into another prime (90864181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45432060 + 45432061.

It is an arithmetic number, because the mean of its divisors is an integer number (45432061).

Almost surely, 2^90864121 is an apocalyptic number.

It is an amenable number.

90864121 is a deficient number, since it is larger than the sum of its proper divisors (1).

90864121 is an equidigital number, since it uses as much as digits as its factorization.

90864121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 90864121 is about 9532.2673588187. The cubic root of 90864121 is about 449.5701590932.

The spelling of 90864121 in words is "ninety million, eight hundred sixty-four thousand, one hundred twenty-one".