18817801250161 has 2 divisors, whose sum is σ = 18817801250162. Its totient is φ = 18817801250160.

The previous prime is 18817801250119. The next prime is 18817801250189. The reversal of 18817801250161 is 16105210871881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9525247690000 + 9292553560161 = 3086300^2 + 3048369^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18817801250161 is a prime.

It is not a weakly prime, because it can be changed into another prime (18817801253161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9408900625080 + 9408900625081.

It is an arithmetic number, because the mean of its divisors is an integer number (9408900625081).

Almost surely, 2^{18817801250161} is an apocalyptic number.

It is an amenable number.

18817801250161 is a deficient number, since it is larger than the sum of its proper divisors (1).

18817801250161 is an equidigital number, since it uses as much as digits as its factorization.

18817801250161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 215040, while the sum is 49.

The spelling of 18817801250161 in words is "eighteen trillion, eight hundred seventeen billion, eight hundred one million, two hundred fifty thousand, one hundred sixty-one".