13921621 has 8 divisors (see below), whose sum is σ = 16007040. Its totient is φ = 11860368.

The previous prime is 13921571. The next prime is 13921643. The reversal of 13921621 is 12612931.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13921621 - 2⁷ = 13921493 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13921651) 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 7 ways as a sum of consecutive naturals, for example, 4786 + ... + 7123.

It is an arithmetic number, because the mean of its divisors is an integer number (2000880).

Almost surely, 2^13921621 is an apocalyptic number.

It is an amenable number.

13921621 is a deficient number, since it is larger than the sum of its proper divisors (2085419).

13921621 is a wasteful number, since it uses less digits than its factorization.

13921621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12083.

The product of its digits is 648, while the sum is 25.

The square root of 13921621 is about 3731.1688517139. The cubic root of 13921621 is about 240.5636117307.

The spelling of 13921621 in words is "thirteen million, nine hundred twenty-one thousand, six hundred twenty-one".