18485854556413 has 2 divisors, whose sum is σ = 18485854556414. Its totient is φ = 18485854556412.

The previous prime is 18485854556359. The next prime is 18485854556447. The reversal of 18485854556413 is 31465545858481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11787706822329 + 6698147734084 = 3433323^2 + 2588078^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18485854556413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18485854526413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9242927278206 + 9242927278207.

It is an arithmetic number, because the mean of its divisors is an integer number (9242927278207).

Almost surely, 2^{18485854556413} is an apocalyptic number.

It is an amenable number.

18485854556413 is a deficient number, since it is larger than the sum of its proper divisors (1).

18485854556413 is an equidigital number, since it uses as much as digits as its factorization.

18485854556413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 368640000, while the sum is 67.

The spelling of 18485854556413 in words is "eighteen trillion, four hundred eighty-five billion, eight hundred fifty-four million, five hundred fifty-six thousand, four hundred thirteen".