13810921 has 2 divisors, whose sum is σ = 13810922. Its totient is φ = 13810920.

The previous prime is 13810883. The next prime is 13810933. The reversal of 13810921 is 12901831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7485696 + 6325225 = 2736^2 + 2515^2 .

It is an emirp because it is prime and its reverse (12901831) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13810921 is a prime.

It is not a weakly prime, because it can be changed into another prime (13810981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6905460 + 6905461.

It is an arithmetic number, because the mean of its divisors is an integer number (6905461).

Almost surely, 2^13810921 is an apocalyptic number.

It is an amenable number.

13810921 is a deficient number, since it is larger than the sum of its proper divisors (1).

13810921 is an equidigital number, since it uses as much as digits as its factorization.

13810921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 13810921 is about 3716.3047506899. The cubic root of 13810921 is about 239.9242874602.

The spelling of 13810921 in words is "thirteen million, eight hundred ten thousand, nine hundred twenty-one".