13780813 has 2 divisors, whose sum is σ = 13780814. Its totient is φ = 13780812.

The previous prime is 13780799. The next prime is 13780817. The reversal of 13780813 is 31808731.

13780813 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., 8749764 + 5031049 = 2958^2 + 2243^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13780813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13780817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6890406 + 6890407.

It is an arithmetic number, because the mean of its divisors is an integer number (6890407).

Almost surely, 2^13780813 is an apocalyptic number.

It is an amenable number.

13780813 is a deficient number, since it is larger than the sum of its proper divisors (1).

13780813 is an equidigital number, since it uses as much as digits as its factorization.

13780813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 13780813 is about 3712.2517425412. The cubic root of 13780813 is about 239.7498145189.

The spelling of 13780813 in words is "thirteen million, seven hundred eighty thousand, eight hundred thirteen".