18780660881 has 2 divisors, whose sum is σ = 18780660882. Its totient is φ = 18780660880.

The previous prime is 18780660841. The next prime is 18780660883. The reversal of 18780660881 is 18806608781.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15777620881 + 3003040000 = 125609^2 + 54800^2 .

It is a cyclic number.

It is not a de Polignac number, because 18780660881 - 2¹⁴ = 18780644497 is a prime.

It is a super-2 number, since 2×18780660881² (a number of 21 digits) contains 22 as substring.

Together with 18780660883, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18780660883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9390330440 + 9390330441.

It is an arithmetic number, because the mean of its divisors is an integer number (9390330441).

Almost surely, 2^18780660881 is an apocalyptic number.

It is an amenable number.

18780660881 is a deficient number, since it is larger than the sum of its proper divisors (1).

18780660881 is an equidigital number, since it uses as much as digits as its factorization.

18780660881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1032192, while the sum is 53.

The spelling of 18780660881 in words is "eighteen billion, seven hundred eighty million, six hundred sixty thousand, eight hundred eighty-one".