21322400 has 72 divisors (see below), whose sum is σ = 56808864. Its totient is φ = 7750400.

The previous prime is 21322391. The next prime is 21322417. The reversal of 21322400 is 422312.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7589 + ... + 10011.

It is an arithmetic number, because the mean of its divisors is an integer number (789012).

Almost surely, 2^21322400 is an apocalyptic number.

21322400 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 21322400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28404432).

21322400 is an abundant number, since it is smaller than the sum of its proper divisors (35486464).

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

21322400 is a wasteful number, since it uses less digits than its factorization.

21322400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2454 (or 2441 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 21322400 is about 4617.6184337816. The cubic root of 21322400 is about 277.2971219568.

Adding to 21322400 its reverse (422312), we get a palindrome (21744712).

The spelling of 21322400 in words is "twenty-one million, three hundred twenty-two thousand, four hundred".