21420972000 has 576 divisors, whose sum is σ = 78817100544. Its totient is φ = 5507251200.

The previous prime is 21420971989. The next prime is 21420972071. The reversal of 21420972000 is 27902412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 200195947 + ... + 200196053.

It is an arithmetic number, because the mean of its divisors is an integer number (136835244).

Almost surely, 2^21420972000 is an apocalyptic number.

21420972000 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 21420972000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39408550272).

21420972000 is an abundant number, since it is smaller than the sum of its proper divisors (57396128544).

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

21420972000 is a wasteful number, since it uses less digits than its factorization.

21420972000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288 (or 267 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The spelling of 21420972000 in words is "twenty-one billion, four hundred twenty million, nine hundred seventy-two thousand".