21226800 has 270 divisors, whose sum is σ = 83480148. Its totient is φ = 4596480.

The previous prime is 21226771. The next prime is 21226823. The reversal of 21226800 is 862212.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 1117191 + ... + 1117209.

Almost surely, 2^21226800 is an apocalyptic number.

21226800 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 21226800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41740074).

21226800 is an abundant number, since it is smaller than the sum of its proper divisors (62253348).

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

21226800 is a wasteful number, since it uses less digits than its factorization.

21226800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73 (or 36 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 21226800 is about 4607.2551481332. The cubic root of 21226800 is about 276.8820760760.

The spelling of 21226800 in words is "twenty-one million, two hundred twenty-six thousand, eight hundred".