18402047820 has 72 divisors (see below), whose sum is σ = 60113363856. Its totient is φ = 4529734272.

The previous prime is 18402047779. The next prime is 18402047821. The reversal of 18402047820 is 2874020481.

18402047820 is a `hidden beast` number, since 184 + 0 + 2 + 0 + 478 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (18402047821) 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 23 ways as a sum of consecutive naturals, for example, 3929722 + ... + 3934401.

Almost surely, 2^18402047820 is an apocalyptic number.

18402047820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18402047820 is an abundant number, since it is smaller than the sum of its proper divisors (41711316036).

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

18402047820 is a wasteful number, since it uses less digits than its factorization.

18402047820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7864151 (or 7864146 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 36.

The spelling of 18402047820 in words is "eighteen billion, four hundred two million, forty-seven thousand, eight hundred twenty".