90989 has 2 divisors, whose sum is σ = 90990. Its totient is φ = 90988.

The previous prime is 90977. The next prime is 90997. The reversal of 90989 is 98909.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84100 + 6889 = 290^2 + 83^2 .

It is an emirp because it is prime and its reverse (98909) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90989 - 2¹⁶ = 25453 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45494 + 45495.

It is an arithmetic number, because the mean of its divisors is an integer number (45495).

2⁹⁰⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

90989 is a deficient number, since it is larger than the sum of its proper divisors (1).

90989 is an equidigital number, since it uses as much as digits as its factorization.

90989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 35.

The square root of 90989 is about 301.6438297065. The cubic root of 90989 is about 44.9776020224.

The spelling of 90989 in words is "ninety thousand, nine hundred eighty-nine".