21616200 has 96 divisors (see below), whose sum is σ = 74474400. Its totient is φ = 5762880.

The previous prime is 21616187. The next prime is 21616201. The reversal of 21616200 is 261612.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (21616201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3399 + ... + 7401.

It is an arithmetic number, because the mean of its divisors is an integer number (775775).

Almost surely, 2^21616200 is an apocalyptic number.

21616200 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 21616200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37237200).

21616200 is an abundant number, since it is smaller than the sum of its proper divisors (52858200).

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

21616200 is a wasteful number, since it uses less digits than its factorization.

21616200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4028 (or 4013 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 21616200 is about 4649.3225312942. The cubic root of 21616200 is about 278.5649364506.

Adding to 21616200 its reverse (261612), we get a palindrome (21877812).

The spelling of 21616200 in words is "twenty-one million, six hundred sixteen thousand, two hundred".