9903989 has 2 divisors, whose sum is σ = 9903990. Its totient is φ = 9903988.

The previous prime is 9903977. The next prime is 9904019. The reversal of 9903989 is 9893099.

It is a happy number.

9903989 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7896100 + 2007889 = 2810^2 + 1417^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9903989 is a prime.

It is a super-2 number, since 2×9903989² = 196177996224242, 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 (9903589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4951994 + 4951995.

It is an arithmetic number, because the mean of its divisors is an integer number (4951995).

Almost surely, 2^9903989 is an apocalyptic number.

It is an amenable number.

9903989 is a deficient number, since it is larger than the sum of its proper divisors (1).

9903989 is an equidigital number, since it uses as much as digits as its factorization.

9903989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 157464, while the sum is 47.

The square root of 9903989 is about 3147.0603743811. The cubic root of 9903989 is about 214.7517524137.

The spelling of 9903989 in words is "nine million, nine hundred three thousand, nine hundred eighty-nine".