13906409 has 12 divisors (see below), whose sum is σ = 15377460. Its totient is φ = 12566400.

The previous prime is 13906397. The next prime is 13906439. The reversal of 13906409 is 90460931.

13906409 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 11256025 + 2650384 = 3355^2 + 1628^2 .

It is not a de Polignac number, because 13906409 - 2⁴ = 13906393 is a prime.

It is a super-2 number, since 2×13906409² = 386776422550562, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13906439) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33797 + ... + 34205.

It is an arithmetic number, because the mean of its divisors is an integer number (1281455).

Almost surely, 2^13906409 is an apocalyptic number.

It is an amenable number.

13906409 is a deficient number, since it is larger than the sum of its proper divisors (1471051).

13906409 is a wasteful number, since it uses less digits than its factorization.

13906409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712 (or 701 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 13906409 is about 3729.1297912516. The cubic root of 13906409 is about 240.4759594056.

The spelling of 13906409 in words is "thirteen million, nine hundred six thousand, four hundred nine".