18888041613509 has 2 divisors, whose sum is σ = 18888041613510. Its totient is φ = 18888041613508.

The previous prime is 18888041613457. The next prime is 18888041613521. The reversal of 18888041613509 is 90531614088881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16169269336609 + 2718772276900 = 4021103^2 + 1648870^2 .

It is a cyclic number.

It is not a de Polignac number, because 18888041613509 - 2²⁴ = 18888024836293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18888041613569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9444020806754 + 9444020806755.

It is an arithmetic number, because the mean of its divisors is an integer number (9444020806755).

Almost surely, 2^{18888041613509} is an apocalyptic number.

It is an amenable number.

18888041613509 is a deficient number, since it is larger than the sum of its proper divisors (1).

18888041613509 is an equidigital number, since it uses as much as digits as its factorization.

18888041613509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13271040, while the sum is 62.

The spelling of 18888041613509 in words is "eighteen trillion, eight hundred eighty-eight billion, forty-one million, six hundred thirteen thousand, five hundred nine".