13816921 has 2 divisors, whose sum is σ = 13816922. Its totient is φ = 13816920.

The previous prime is 13816897. The next prime is 13816931. The reversal of 13816921 is 12961831.

13816921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9241600 + 4575321 = 3040^2 + 2139^2 .

It is a cyclic number.

It is not a de Polignac number, because 13816921 - 2⁹ = 13816409 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13816931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6908460 + 6908461.

It is an arithmetic number, because the mean of its divisors is an integer number (6908461).

Almost surely, 2^13816921 is an apocalyptic number.

It is an amenable number.

13816921 is a deficient number, since it is larger than the sum of its proper divisors (1).

13816921 is an equidigital number, since it uses as much as digits as its factorization.

13816921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592, while the sum is 31.

The square root of 13816921 is about 3717.1119165287. Note that the first 3 decimals coincide. The cubic root of 13816921 is about 239.9590265701.

The spelling of 13816921 in words is "thirteen million, eight hundred sixteen thousand, nine hundred twenty-one".