18477781151 has 6 divisors (see below), whose sum is σ = 19628646720. Its totient is φ = 17390852576.

The previous prime is 18477781139. The next prime is 18477781171. The reversal of 18477781151 is 15118777481.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-18477781151 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18477781151.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18477781111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 31968191 + ... + 31968768.

It is an arithmetic number, because the mean of its divisors is an integer number (3271441120).

Almost surely, 2^18477781151 is an apocalyptic number.

18477781151 is a deficient number, since it is larger than the sum of its proper divisors (1150865569).

18477781151 is an equidigital number, since it uses as much as digits as its factorization.

18477781151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63936993 (or 63936976 counting only the distinct ones).

The product of its digits is 439040, while the sum is 50.

The spelling of 18477781151 in words is "eighteen billion, four hundred seventy-seven million, seven hundred eighty-one thousand, one hundred fifty-one".