21238200 has 288 divisors, whose sum is σ = 81244800. Its totient is φ = 5132160.

The previous prime is 21238157. The next prime is 21238207. The reversal of 21238200 is 283212.

It is a happy number.

It is a super-2 number, since 2×21238200² = 902122278480000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21238207) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 923389 + ... + 923411.

It is an arithmetic number, because the mean of its divisors is an integer number (282100).

Almost surely, 2^21238200 is an apocalyptic number.

21238200 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 21238200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40622400).

21238200 is an abundant number, since it is smaller than the sum of its proper divisors (60006600).

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

21238200 is a wasteful number, since it uses less digits than its factorization.

21238200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73 (or 52 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 21238200 is about 4608.4921612172. The cubic root of 21238200 is about 276.9316343509.

The spelling of 21238200 in words is "twenty-one million, two hundred thirty-eight thousand, two hundred".