18420747840 has 840 divisors, whose sum is σ = 76024605888. Its totient is φ = 4190883840.

The previous prime is 18420747833. The next prime is 18420747871. The reversal of 18420747840 is 4874702481.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 347561254 + ... + 347561306.

Almost surely, 2^18420747840 is an apocalyptic number.

18420747840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18420747840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38012302944).

18420747840 is an abundant number, since it is smaller than the sum of its proper divisors (57603858048).

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

18420747840 is a wasteful number, since it uses less digits than its factorization.

18420747840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169 (or 97 counting only the distinct ones).

The product of its (nonzero) digits is 401408, while the sum is 45.

The spelling of 18420747840 in words is "eighteen billion, four hundred twenty million, seven hundred forty-seven thousand, eight hundred forty".