13909531 has 4 divisors (see below), whose sum is σ = 14389200. Its totient is φ = 13429864.

The previous prime is 13909529. The next prime is 13909541. The reversal of 13909531 is 13590931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13590931 = 257 ⋅52883.

It is a cyclic number.

It is not a de Polignac number, because 13909531 - 2¹ = 13909529 is a prime.

It is a super-2 number, since 2×13909531² = 386950105279922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13909493 and 13909502.

It is not an unprimeable number, because it can be changed into a prime (13909541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 239791 + ... + 239848.

It is an arithmetic number, because the mean of its divisors is an integer number (3597300).

Almost surely, 2^13909531 is an apocalyptic number.

13909531 is a deficient number, since it is larger than the sum of its proper divisors (479669).

13909531 is an equidigital number, since it uses as much as digits as its factorization.

13909531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 479668.

The product of its (nonzero) digits is 3645, while the sum is 31.

The square root of 13909531 is about 3729.5483640784. The cubic root of 13909531 is about 240.4939537411.

The spelling of 13909531 in words is "thirteen million, nine hundred nine thousand, five hundred thirty-one".