21225991680000 has 1560 divisors, whose sum is σ = 80335673418000. Its totient is φ = 5597724672000.

The previous prime is 21225991679999. The next prime is 21225991680001. The reversal of 21225991680000 is 8619952212.

It is a happy number.

21225991680000 is a `hidden beast` number, since 21 + 22 + 599 + 16 + 8 + 0 + 0 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (21225991679999) and next prime (21225991680001).

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

It is not an unprimeable number, because it can be changed into a prime (21225991680001) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 92689919886 + ... + 92689920114.

It is an arithmetic number, because the mean of its divisors is an integer number (51497226550).

Almost surely, 2^{21225991680000} is an apocalyptic number.

21225991680000 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 21225991680000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40167836709000).

21225991680000 is an abundant number, since it is smaller than the sum of its proper divisors (59109681738000).

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

21225991680000 is an frugal number, since it uses more digits than its factorization.

21225991680000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 45.

The spelling of 21225991680000 in words is "twenty-one trillion, two hundred twenty-five billion, nine hundred ninety-one million, six hundred eighty thousand".