91022989 has 2 divisors, whose sum is σ = 91022990. Its totient is φ = 91022988.

The previous prime is 91022929. The next prime is 91023007. The reversal of 91022989 is 98922019.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71149225 + 19873764 = 8435^2 + 4458^2 .

It is a cyclic number.

It is not a de Polignac number, because 91022989 - 2²⁵ = 57468557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91022929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45511494 + 45511495.

It is an arithmetic number, because the mean of its divisors is an integer number (45511495).

Almost surely, 2^91022989 is an apocalyptic number.

It is an amenable number.

91022989 is a deficient number, since it is larger than the sum of its proper divisors (1).

91022989 is an equidigital number, since it uses as much as digits as its factorization.

91022989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 91022989 is about 9540.5968890840. The cubic root of 91022989 is about 449.8320179596.

The spelling of 91022989 in words is "ninety-one million, twenty-two thousand, nine hundred eighty-nine".