13799921 has 2 divisors, whose sum is σ = 13799922. Its totient is φ = 13799920.

The previous prime is 13799917. The next prime is 13799939. The reversal of 13799921 is 12999731.

13799921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13359025 + 440896 = 3655^2 + 664^2 .

It is an emirp because it is prime and its reverse (12999731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13799921 - 2² = 13799917 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (13799021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6899960 + 6899961.

It is an arithmetic number, because the mean of its divisors is an integer number (6899961).

Almost surely, 2^13799921 is an apocalyptic number.

It is an amenable number.

13799921 is a deficient number, since it is larger than the sum of its proper divisors (1).

13799921 is an equidigital number, since it uses as much as digits as its factorization.

13799921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30618, while the sum is 41.

The square root of 13799921 is about 3714.8244911436. The cubic root of 13799921 is about 239.8605729513.

The spelling of 13799921 in words is "thirteen million, seven hundred ninety-nine thousand, nine hundred twenty-one".