9966989 has 2 divisors, whose sum is σ = 9966990. Its totient is φ = 9966988.

The previous prime is 9966967. The next prime is 9966997. The reversal of 9966989 is 9896699.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6086089 + 3880900 = 2467^2 + 1970^2 .

It is an emirp because it is prime and its reverse (9896699) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9966989 - 2¹² = 9962893 is a prime.

It is a super-2 number, since 2×9966989² = 198681739452242, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9966389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4983494 + 4983495.

It is an arithmetic number, because the mean of its divisors is an integer number (4983495).

Almost surely, 2^9966989 is an apocalyptic number.

It is an amenable number.

9966989 is a deficient number, since it is larger than the sum of its proper divisors (1).

9966989 is an equidigital number, since it uses as much as digits as its factorization.

9966989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1889568, while the sum is 56.

The square root of 9966989 is about 3157.0538481312. The cubic root of 9966989 is about 215.2061408515.

The spelling of 9966989 in words is "nine million, nine hundred sixty-six thousand, nine hundred eighty-nine".