9991489 has 2 divisors, whose sum is σ = 9991490. Its totient is φ = 9991488.

The previous prime is 9991469. The next prime is 9991543. The reversal of 9991489 is 9841999.

9991489 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., 9641025 + 350464 = 3105^2 + 592^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9991489 is a prime.

It is a Chen prime.

It is a nialpdrome in base 16.

It is not a weakly prime, because it can be changed into another prime (9991409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995744 + 4995745.

It is an arithmetic number, because the mean of its divisors is an integer number (4995745).

Almost surely, 2^9991489 is an apocalyptic number.

It is an amenable number.

9991489 is a deficient number, since it is larger than the sum of its proper divisors (1).

9991489 is an equidigital number, since it uses as much as digits as its factorization.

9991489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 209952, while the sum is 49.

The square root of 9991489 is about 3160.9316664553. The cubic root of 9991489 is about 215.3823303427.

The spelling of 9991489 in words is "nine million, nine hundred ninety-one thousand, four hundred eighty-nine".