18212421864 has 256 divisors, whose sum is σ = 57708564480. Its totient is φ = 4662282240.

The previous prime is 18212421841. The next prime is 18212421881. The reversal of 18212421864 is 46812421281.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 10388412 + ... + 10390164.

It is an arithmetic number, because the mean of its divisors is an integer number (225424080).

Almost surely, 2^18212421864 is an apocalyptic number.

18212421864 is a gapful number since it is divisible by the number (14) 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 18212421864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28854282240).

18212421864 is an abundant number, since it is smaller than the sum of its proper divisors (39496142616).

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

18212421864 is a wasteful number, since it uses less digits than its factorization.

18212421864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1920 (or 1916 counting only the distinct ones).

The product of its digits is 49152, while the sum is 39.

The spelling of 18212421864 in words is "eighteen billion, two hundred twelve million, four hundred twenty-one thousand, eight hundred sixty-four".