21332100 has 72 divisors (see below), whose sum is σ = 62197408. Its totient is φ = 5644800.

The previous prime is 21332089. The next prime is 21332119. The reversal of 21332100 is 123312.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 63132 + ... + 63468.

Almost surely, 2^21332100 is an apocalyptic number.

21332100 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 21332100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31098704).

21332100 is an abundant number, since it is smaller than the sum of its proper divisors (40865308).

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

21332100 is a wasteful number, since it uses less digits than its factorization.

21332100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 565 (or 558 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 21332100 is about 4618.6686393375. The cubic root of 21332100 is about 277.3391649774.

Adding to 21332100 its reverse (123312), we get a palindrome (21455412).

The spelling of 21332100 in words is "twenty-one million, three hundred thirty-two thousand, one hundred".