13538813 has 2 divisors, whose sum is σ = 13538814. Its totient is φ = 13538812.

The previous prime is 13538779. The next prime is 13538821. The reversal of 13538813 is 31883531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7198489 + 6340324 = 2683^2 + 2518^2 .

It is a cyclic number.

It is not a de Polignac number, because 13538813 - 2⁸ = 13538557 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 13538813.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13538843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6769406 + 6769407.

It is an arithmetic number, because the mean of its divisors is an integer number (6769407).

Almost surely, 2^13538813 is an apocalyptic number.

It is an amenable number.

13538813 is a deficient number, since it is larger than the sum of its proper divisors (1).

13538813 is an equidigital number, since it uses as much as digits as its factorization.

13538813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 32.

The square root of 13538813 is about 3679.5126035930. The cubic root of 13538813 is about 238.3381312980.

The spelling of 13538813 in words is "thirteen million, five hundred thirty-eight thousand, eight hundred thirteen".