13937921 has 2 divisors, whose sum is σ = 13937922. Its totient is φ = 13937920.

The previous prime is 13937851. The next prime is 13937923. The reversal of 13937921 is 12973931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10080625 + 3857296 = 3175^2 + 1964^2 .

It is an emirp because it is prime and its reverse (12973931) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13937921 is a prime.

Together with 13937923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13937923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6968960 + 6968961.

It is an arithmetic number, because the mean of its divisors is an integer number (6968961).

Almost surely, 2^13937921 is an apocalyptic number.

It is an amenable number.

13937921 is a deficient number, since it is larger than the sum of its proper divisors (1).

13937921 is an equidigital number, since it uses as much as digits as its factorization.

13937921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10206, while the sum is 35.

The square root of 13937921 is about 3733.3525148317. The cubic root of 13937921 is about 240.6574623320.

The spelling of 13937921 in words is "thirteen million, nine hundred thirty-seven thousand, nine hundred twenty-one".