21322100 has 36 divisors (see below), whose sum is σ = 46872000. Its totient is φ = 8417760.

The previous prime is 21322099. The next prime is 21322117. The reversal of 21322100 is 122312.

It is a happy number.

It is a congruent number.

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, 6551 + ... + 9249.

It is an arithmetic number, because the mean of its divisors is an integer number (1302000).

Almost surely, 2^21322100 is an apocalyptic number.

21322100 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 21322100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23436000).

21322100 is an abundant number, since it is smaller than the sum of its proper divisors (25549900).

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

21322100 is a wasteful number, since it uses less digits than its factorization.

21322100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2792 (or 2785 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 21322100 is about 4617.5859493896. The cubic root of 21322100 is about 277.2958214540.

Adding to 21322100 its reverse (122312), we get a palindrome (21444412).

The spelling of 21322100 in words is "twenty-one million, three hundred twenty-two thousand, one hundred".