18177557813 has 2 divisors, whose sum is σ = 18177557814. Its totient is φ = 18177557812.

The previous prime is 18177557809. The next prime is 18177557821. The reversal of 18177557813 is 31875577181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16011865444 + 2165692369 = 126538^2 + 46537^2 .

It is a cyclic number.

It is not a de Polignac number, because 18177557813 - 2² = 18177557809 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18177557833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9088778906 + 9088778907.

It is an arithmetic number, because the mean of its divisors is an integer number (9088778907).

Almost surely, 2^18177557813 is an apocalyptic number.

It is an amenable number.

18177557813 is a deficient number, since it is larger than the sum of its proper divisors (1).

18177557813 is an equidigital number, since it uses as much as digits as its factorization.

18177557813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1646400, while the sum is 53.

The spelling of 18177557813 in words is "eighteen billion, one hundred seventy-seven million, five hundred fifty-seven thousand, eight hundred thirteen".