21940800 has 168 divisors, whose sum is σ = 82393536. Its totient is φ = 5007360.

The previous prime is 21940799. The next prime is 21940813. The reversal of 21940800 is 804912.

21940800 = T₆₁ + T₆₂ + ... + T₅₀₈.

It is a tau number, because it is divible by the number of its divisors (168).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33274 + ... + 33926.

Almost surely, 2^21940800 is an apocalyptic number.

21940800 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 21940800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41196768).

21940800 is an abundant number, since it is smaller than the sum of its proper divisors (60452736).

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

21940800 is a wasteful number, since it uses less digits than its factorization.

21940800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685 (or 670 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 21940800 is about 4684.1007674900. The cubic root of 21940800 is about 279.9523728516.

The spelling of 21940800 in words is "twenty-one million, nine hundred forty thousand, eight hundred".