21312022200 has 192 divisors, whose sum is σ = 77546703360. Its totient is φ = 4739627520.

The previous prime is 21312022187. The next prime is 21312022213. The reversal of 21312022200 is 222021312.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21312022187) and next prime (21312022213).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21312022200.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 86829 + ... + 223971.

It is an arithmetic number, because the mean of its divisors is an integer number (403889080).

Almost surely, 2^21312022200 is an apocalyptic number.

21312022200 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 21312022200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38773351680).

21312022200 is an abundant number, since it is smaller than the sum of its proper divisors (56234681160).

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

21312022200 is a wasteful number, since it uses less digits than its factorization.

21312022200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137206 (or 137197 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 21312022200 its reverse (222021312), we get a palindrome (21534043512).

The spelling of 21312022200 in words is "twenty-one billion, three hundred twelve million, twenty-two thousand, two hundred".