13406921 has 12 divisors (see below), whose sum is σ = 14842800. Its totient is φ = 12100440.

The previous prime is 13406917. The next prime is 13406929. The reversal of 13406921 is 12960431.

It is not a de Polignac number, because 13406921 - 2² = 13406917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13406929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21350 + ... + 21968.

It is an arithmetic number, because the mean of its divisors is an integer number (1236900).

Almost surely, 2^13406921 is an apocalyptic number.

13406921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13406921 is a deficient number, since it is larger than the sum of its proper divisors (1435879).

13406921 is a wasteful number, since it uses less digits than its factorization.

13406921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 820 (or 809 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 13406921 is about 3661.5462580719. The cubic root of 13406921 is about 237.5616593370.

The spelling of 13406921 in words is "thirteen million, four hundred six thousand, nine hundred twenty-one".