21100200 has 192 divisors, whose sum is σ = 74995200. Its totient is φ = 4857600.

The previous prime is 21100193. The next prime is 21100207. The reversal of 21100200 is 200112.

21100200 = 255² + 256² + ... + 430².

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21100193) and next prime (21100207).

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100207) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 151731 + ... + 151869.

It is an arithmetic number, because the mean of its divisors is an integer number (390600).

Almost surely, 2^21100200 is an apocalyptic number.

21100200 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 21100200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37497600).

21100200 is an abundant number, since it is smaller than the sum of its proper divisors (53895000).

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

21100200 is a wasteful number, since it uses less digits than its factorization.

21100200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192 (or 183 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

The square root of 21100200 is about 4593.4954011080. The cubic root of 21100200 is about 276.3305219022.

Adding to 21100200 its reverse (200112), we get a palindrome (21300312).

The spelling of 21100200 in words is "twenty-one million, one hundred thousand, two hundred".