13218825817 has 2 divisors, whose sum is σ = 13218825818. Its totient is φ = 13218825816.

The previous prime is 13218825803. The next prime is 13218825821. The reversal of 13218825817 is 71852881231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9531421641 + 3687404176 = 97629^2 + 60724^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13218825817 is a prime.

It is not a weakly prime, because it can be changed into another prime (13218825517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6609412908 + 6609412909.

It is an arithmetic number, because the mean of its divisors is an integer number (6609412909).

Almost surely, 2^13218825817 is an apocalyptic number.

It is an amenable number.

13218825817 is a deficient number, since it is larger than the sum of its proper divisors (1).

13218825817 is an equidigital number, since it uses as much as digits as its factorization.

13218825817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 215040, while the sum is 46.

The spelling of 13218825817 in words is "thirteen billion, two hundred eighteen million, eight hundred twenty-five thousand, eight hundred seventeen".