16694989 has 2 divisors, whose sum is σ = 16694990. Its totient is φ = 16694988.

The previous prime is 16694963. The next prime is 16694999. The reversal of 16694989 is 98949661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15539364 + 1155625 = 3942^2 + 1075^2 .

It is an emirp because it is prime and its reverse (98949661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16694989 - 2⁷ = 16694861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16694929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8347494 + 8347495.

It is an arithmetic number, because the mean of its divisors is an integer number (8347495).

Almost surely, 2^16694989 is an apocalyptic number.

It is an amenable number.

16694989 is a deficient number, since it is larger than the sum of its proper divisors (1).

16694989 is an equidigital number, since it uses as much as digits as its factorization.

16694989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 839808, while the sum is 52.

The square root of 16694989 is about 4085.9501954870. The cubic root of 16694989 is about 255.5810867232.

The spelling of 16694989 in words is "sixteen million, six hundred ninety-four thousand, nine hundred eighty-nine".