21226915600 has 240 divisors, whose sum is σ = 57381755904. Its totient is φ = 7479360000.

The previous prime is 21226915559. The next prime is 21226915607. The reversal of 21226915600 is 651962212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21226915607) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 28568829 + ... + 28569571.

Almost surely, 2^21226915600 is an apocalyptic number.

21226915600 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 21226915600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28690877952).

21226915600 is an abundant number, since it is smaller than the sum of its proper divisors (36154840304).

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

21226915600 is a wasteful number, since it uses less digits than its factorization.

21226915600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 966 (or 955 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 34.

The spelling of 21226915600 in words is "twenty-one billion, two hundred twenty-six million, nine hundred fifteen thousand, six hundred".