21310200 has 72 divisors (see below), whose sum is σ = 71572800. Its totient is φ = 5682240.

The previous prime is 21310199. The next prime is 21310207. The reversal of 21310200 is 201312.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a zygodrome in base 3.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21310207) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4120 + ... + 7719.

Almost surely, 2^21310200 is an apocalyptic number.

21310200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21310200 is an abundant number, since it is smaller than the sum of its proper divisors (50262600).

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

21310200 is a wasteful number, since it uses less digits than its factorization.

21310200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11861 (or 11849 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 21310200 is about 4616.2972174677. The cubic root of 21310200 is about 277.2442249985.

Adding to 21310200 its reverse (201312), we get a palindrome (21511512).

The spelling of 21310200 in words is "twenty-one million, three hundred ten thousand, two hundred".