90590989 has 2 divisors, whose sum is σ = 90590990. Its totient is φ = 90590988.

The previous prime is 90590971. The next prime is 90591013. The reversal of 90590989 is 98909509.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71537764 + 19053225 = 8458^2 + 4365^2 .

It is an emirp because it is prime and its reverse (98909509) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90590989 - 2⁹ = 90590477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90590089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45295494 + 45295495.

It is an arithmetic number, because the mean of its divisors is an integer number (45295495).

Almost surely, 2^90590989 is an apocalyptic number.

It is an amenable number.

90590989 is a deficient number, since it is larger than the sum of its proper divisors (1).

90590989 is an equidigital number, since it uses as much as digits as its factorization.

90590989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 262440, while the sum is 49.

The square root of 90590989 is about 9517.9298694622. The cubic root of 90590989 is about 449.1192468361.

The spelling of 90590989 in words is "ninety million, five hundred ninety thousand, nine hundred eighty-nine".