21221976000 has 224 divisors, whose sum is σ = 71040760128. Its totient is φ = 5581209600.

The previous prime is 21221975989. The next prime is 21221976047. The reversal of 21221976000 is 67912212.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1745944 + ... + 1758056.

Almost surely, 2^21221976000 is an apocalyptic number.

21221976000 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 21221976000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35520380064).

21221976000 is an abundant number, since it is smaller than the sum of its proper divisors (49818784128).

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

21221976000 is a wasteful number, since it uses less digits than its factorization.

21221976000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12216 (or 12196 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 30.

The spelling of 21221976000 in words is "twenty-one billion, two hundred twenty-one million, nine hundred seventy-six thousand".