16904989 has 2 divisors, whose sum is σ = 16904990. Its totient is φ = 16904988.

The previous prime is 16904983. The next prime is 16905017. The reversal of 16904989 is 98940961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11168964 + 5736025 = 3342^2 + 2395^2 .

It is a cyclic number.

It is not a de Polignac number, because 16904989 - 2⁷ = 16904861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16904983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8452494 + 8452495.

It is an arithmetic number, because the mean of its divisors is an integer number (8452495).

Almost surely, 2^16904989 is an apocalyptic number.

It is an amenable number.

16904989 is a deficient number, since it is larger than the sum of its proper divisors (1).

16904989 is an equidigital number, since it uses as much as digits as its factorization.

16904989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 139968, while the sum is 46.

The square root of 16904989 is about 4111.5677058757. The cubic root of 16904989 is about 256.6482442129.

The spelling of 16904989 in words is "sixteen million, nine hundred four thousand, nine hundred eighty-nine".