13664789 has 2 divisors, whose sum is σ = 13664790. Its totient is φ = 13664788.

The previous prime is 13664759. The next prime is 13664801. The reversal of 13664789 is 98746631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11444689 + 2220100 = 3383^2 + 1490^2 .

It is a cyclic number.

It is not a de Polignac number, because 13664789 - 2⁸ = 13664533 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13664759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6832394 + 6832395.

It is an arithmetic number, because the mean of its divisors is an integer number (6832395).

Almost surely, 2^13664789 is an apocalyptic number.

It is an amenable number.

13664789 is a deficient number, since it is larger than the sum of its proper divisors (1).

13664789 is an equidigital number, since it uses as much as digits as its factorization.

13664789 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 44.

The square root of 13664789 is about 3696.5915381605. The cubic root of 13664789 is about 239.0750801388.

The spelling of 13664789 in words is "thirteen million, six hundred sixty-four thousand, seven hundred eighty-nine".