21332500 has 120 divisors (see below), whose sum is σ = 56681856. Its totient is φ = 6864000.

The previous prime is 21332471. The next prime is 21332503. The reversal of 21332500 is 523312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21332503) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 402474 + ... + 402526.

Almost surely, 2^21332500 is an apocalyptic number.

21332500 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 21332500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28340928).

21332500 is an abundant number, since it is smaller than the sum of its proper divisors (35349356).

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

21332500 is a wasteful number, since it uses less digits than its factorization.

21332500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 16.

The square root of 21332500 is about 4618.7119416565. The cubic root of 21332500 is about 277.3408984366.

Adding to 21332500 its reverse (523312), we get a palindrome (21855812).

The spelling of 21332500 in words is "twenty-one million, three hundred thirty-two thousand, five hundred".