21980836800 has 504 divisors, whose sum is σ = 89096703696. Its totient is φ = 5091655680.

The previous prime is 21980836799. The next prime is 21980836859. The reversal of 21980836800 is 863808912.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 3178947 + ... + 3185853.

It is an arithmetic number, because the mean of its divisors is an integer number (176779174).

Almost surely, 2^21980836800 is an apocalyptic number.

21980836800 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 21980836800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44548351848).

21980836800 is an abundant number, since it is smaller than the sum of its proper divisors (67115866896).

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

21980836800 is a wasteful number, since it uses less digits than its factorization.

21980836800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6965 (or 6947 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 21980836800 in words is "twenty-one billion, nine hundred eighty million, eight hundred thirty-six thousand, eight hundred".