18721835166872 has 32 divisors (see below), whose sum is σ = 35386431275520. Its totient is φ = 9285480933120.

The previous prime is 18721835166869. The next prime is 18721835166929. The reversal of 18721835166872 is 27866153812781.

It is a super-2 number, since 2×18721835166872² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18721835166799 and 18721835166808.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 3754868 + ... + 7179324.

It is an arithmetic number, because the mean of its divisors is an integer number (1105825977360).

Almost surely, 2^{18721835166872} is an apocalyptic number.

It is an amenable number.

18721835166872 is a deficient number, since it is larger than the sum of its proper divisors (16664596108648).

18721835166872 is a wasteful number, since it uses less digits than its factorization.

18721835166872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3429971 (or 3429967 counting only the distinct ones).

The product of its digits is 54190080, while the sum is 65.

The spelling of 18721835166872 in words is "eighteen trillion, seven hundred twenty-one billion, eight hundred thirty-five million, one hundred sixty-six thousand, eight hundred seventy-two".