18816722477568 has 120 divisors (see below), whose sum is σ = 55196603732556. Its totient is φ = 6169417113600.

The previous prime is 18816722477561. The next prime is 18816722477591. The reversal of 18816722477568 is 86577422761881.

18816722477568 is a `hidden beast` number, since 1 + 8 + 8 + 16 + 7 + 2 + 2 + 47 + 7 + 568 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 12227274549504 + 6589447928064 = 3496752^2 + 2566992^2 .

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 18816722477496 and 18816722477505.

It is not an unprimeable number, because it can be changed into a prime (18816722477561) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33190143 + ... + 33752318.

Almost surely, 2^{18816722477568} is an apocalyptic number.

18816722477568 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

18816722477568 is an abundant number, since it is smaller than the sum of its proper divisors (36379881254988).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18816722477568 is an equidigital number, since it uses as much as digits as its factorization.

18816722477568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66942546 (or 66942527 counting only the distinct ones).

The product of its digits is 505774080, while the sum is 72.

The spelling of 18816722477568 in words is "eighteen trillion, eight hundred sixteen billion, seven hundred twenty-two million, four hundred seventy-seven thousand, five hundred sixty-eight".