21819918000 has 160 divisors (see below), whose sum is σ = 70484506560. Its totient is φ = 5807308800.

The previous prime is 21819917983. The next prime is 21819918011. The reversal of 21819918000 is 81991812.

It is a super-2 number, since 2×21819918000² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21819918000.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3338736 + ... + 3345264.

It is an arithmetic number, because the mean of its divisors is an integer number (440528166).

Almost surely, 2^21819918000 is an apocalyptic number.

21819918000 is a gapful number since it is divisible by the number (20) 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 21819918000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35242253280).

21819918000 is an abundant number, since it is smaller than the sum of its proper divisors (48664588560).

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

21819918000 is a wasteful number, since it uses less digits than its factorization.

21819918000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7112 (or 7096 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 39.

The spelling of 21819918000 in words is "twenty-one billion, eight hundred nineteen million, nine hundred eighteen thousand".