13909685 has 4 divisors (see below), whose sum is σ = 16691628. Its totient is φ = 11127744.

The previous prime is 13909673. The next prime is 13909699. The reversal of 13909685 is 58690931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58690931 = 13 ⋅4514687.

It can be written as a sum of positive squares in 2 ways, for example, as 9690769 + 4218916 = 3113^2 + 2054^2 .

It is a cyclic number.

It is not a de Polignac number, because 13909685 - 2²⁰ = 12861109 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1390964 + ... + 1390973.

It is an arithmetic number, because the mean of its divisors is an integer number (4172907).

Almost surely, 2^13909685 is an apocalyptic number.

It is an amenable number.

13909685 is a deficient number, since it is larger than the sum of its proper divisors (2781943).

13909685 is an equidigital number, since it uses as much as digits as its factorization.

13909685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2781942.

The product of its (nonzero) digits is 58320, while the sum is 41.

The square root of 13909685 is about 3729.5690099528. The cubic root of 13909685 is about 240.4948412844.

The spelling of 13909685 in words is "thirteen million, nine hundred nine thousand, six hundred eighty-five".