18889266658061 has 2 divisors, whose sum is σ = 18889266658062. Its totient is φ = 18889266658060.

The previous prime is 18889266658057. The next prime is 18889266658069. The reversal of 18889266658061 is 16085666298881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18171847494025 + 717419164036 = 4262845^2 + 847006^2 .

It is an emirp because it is prime and its reverse (16085666298881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18889266658061 - 2² = 18889266658057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18889266658061.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18889266658069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9444633329030 + 9444633329031.

It is an arithmetic number, because the mean of its divisors is an integer number (9444633329031).

Almost surely, 2^{18889266658061} is an apocalyptic number.

It is an amenable number.

18889266658061 is a deficient number, since it is larger than the sum of its proper divisors (1).

18889266658061 is an equidigital number, since it uses as much as digits as its factorization.

18889266658061 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 477757440, while the sum is 74.

The spelling of 18889266658061 in words is "eighteen trillion, eight hundred eighty-nine billion, two hundred sixty-six million, six hundred fifty-eight thousand, sixty-one".