13689729 has 10 divisors (see below), whose sum is σ = 20450210. Its totient is φ = 9126432.

The previous prime is 13689721. The next prime is 13689733. The reversal of 13689729 is 92798631.

13689729 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 only one way, i.e., 11209104 + 2480625 = 3348^2 + 1575^2 .

It is not a de Polignac number, because 13689729 - 2³ = 13689721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13689721) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 84424 + ... + 84585.

It is an arithmetic number, because the mean of its divisors is an integer number (2045021).

Almost surely, 2^13689729 is an apocalyptic number.

It is an amenable number.

13689729 is a deficient number, since it is larger than the sum of its proper divisors (6760481).

13689729 is an equidigital number, since it uses as much as digits as its factorization.

13689729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 169021 (or 169012 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 13689729 is about 3699.9633781971. The cubic root of 13689729 is about 239.2204393466.

It can be divided in two parts, 13689 and 729, that multiplied together give a square (9979281 = 3159²).

The spelling of 13689729 in words is "thirteen million, six hundred eighty-nine thousand, seven hundred twenty-nine".