13664729 has 8 divisors (see below), whose sum is σ = 15114120. Its totient is φ = 12272256.

The previous prime is 13664723. The next prime is 13664747. The reversal of 13664729 is 92746631.

13664729 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 3115225 + 10549504 = 1765^2 + 3248^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13664729 - 2⁸ = 13664473 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13664692 and 13664701.

It is not an unprimeable number, because it can be changed into a prime (13664723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13724 + ... + 14685.

It is an arithmetic number, because the mean of its divisors is an integer number (1889265).

Almost surely, 2^13664729 is an apocalyptic number.

It is an amenable number.

13664729 is a deficient number, since it is larger than the sum of its proper divisors (1449391).

13664729 is a wasteful number, since it uses less digits than its factorization.

13664729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28459.

The product of its digits is 54432, while the sum is 38.

The square root of 13664729 is about 3696.5834225674. The cubic root of 13664729 is about 239.0747302243.

The spelling of 13664729 in words is "thirteen million, six hundred sixty-four thousand, seven hundred twenty-nine".