21973600 has 108 divisors (see below), whose sum is σ = 59222772. Its totient is φ = 7955200.

The previous prime is 21973591. The next prime is 21973607. The reversal of 21973600 is 637912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21973607) by changing a digit.

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 17 ways as a sum of consecutive naturals, for example, 96687 + ... + 96913.

It is an arithmetic number, because the mean of its divisors is an integer number (548359).

Almost surely, 2^21973600 is an apocalyptic number.

21973600 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 21973600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29611386).

21973600 is an abundant number, since it is smaller than the sum of its proper divisors (37249172).

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

21973600 is a wasteful number, since it uses less digits than its factorization.

21973600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269 (or 245 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 28.

The square root of 21973600 is about 4687.6006655858. The cubic root of 21973600 is about 280.0918066298.

The spelling of 21973600 in words is "twenty-one million, nine hundred seventy-three thousand, six hundred".