18780660865 has 32 divisors (see below), whose sum is σ = 24502072320. Its totient is φ = 13772493504.

The previous prime is 18780660841. The next prime is 18780660881. The reversal of 18780660865 is 56806608781.

It is a cyclic number.

It is not a de Polignac number, because 18780660865 - 2⁷ = 18780660737 is a prime.

It is a super-2 number, since 2×18780660865² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 415612 + ... + 458578.

It is an arithmetic number, because the mean of its divisors is an integer number (765689760).

Almost surely, 2^18780660865 is an apocalyptic number.

It is an amenable number.

18780660865 is a deficient number, since it is larger than the sum of its proper divisors (5721411455).

18780660865 is a wasteful number, since it uses less digits than its factorization.

18780660865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43141.

The product of its (nonzero) digits is 3870720, while the sum is 55.

The spelling of 18780660865 in words is "eighteen billion, seven hundred eighty million, six hundred sixty thousand, eight hundred sixty-five".