21244800 has 96 divisors (see below), whose sum is σ = 70006680. Its totient is φ = 5662720.

The previous prime is 21244787. The next prime is 21244807. The reversal of 21244800 is 844212.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21244807) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8494 + ... + 10706.

Almost surely, 2^21244800 is an apocalyptic number.

21244800 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 21244800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35003340).

21244800 is an abundant number, since it is smaller than the sum of its proper divisors (48761880).

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

21244800 is a wasteful number, since it uses less digits than its factorization.

21244800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2240 (or 2223 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 21.

The square root of 21244800 is about 4609.2081749472. The cubic root of 21244800 is about 276.9603178786.

The spelling of 21244800 in words is "twenty-one million, two hundred forty-four thousand, eight hundred".