989917 has 2 divisors, whose sum is σ = 989918. Its totient is φ = 989916.

The previous prime is 989909. The next prime is 989921. The reversal of 989917 is 719989.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 962361 + 27556 = 981^2 + 166^2 .

It is an emirp because it is prime and its reverse (719989) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 989917 - 2³ = 989909 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (989977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494958 + 494959.

It is an arithmetic number, because the mean of its divisors is an integer number (494959).

2⁹⁸⁹⁹¹⁷ is an apocalyptic number.

It is an amenable number.

989917 is a deficient number, since it is larger than the sum of its proper divisors (1).

989917 is an equidigital number, since it uses as much as digits as its factorization.

989917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 43.

The square root of 989917 is about 994.9457271630. The cubic root of 989917 is about 99.6627639972.

The spelling of 989917 in words is "nine hundred eighty-nine thousand, nine hundred seventeen".