13906405 has 16 divisors (see below), whose sum is σ = 17209584. Its totient is φ = 10782720.

The previous prime is 13906397. The next prime is 13906439. The reversal of 13906405 is 50460931.

13906405 is digitally balanced in base 2, 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 8 ways, for example, as 15876 + 13890529 = 126^2 + 3727^2 .

It is not a de Polignac number, because 13906405 - 2³ = 13906397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25435 + ... + 25975.

It is an arithmetic number, because the mean of its divisors is an integer number (1075599).

Almost surely, 2^13906405 is an apocalyptic number.

It is an amenable number.

13906405 is a deficient number, since it is larger than the sum of its proper divisors (3303179).

13906405 is an equidigital number, since it uses as much as digits as its factorization.

13906405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696.

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 13906405 is about 3729.1292549334. The cubic root of 13906405 is about 240.4759363490.

The spelling of 13906405 in words is "thirteen million, nine hundred six thousand, four hundred five".