201221212200 has 192 divisors, whose sum is σ = 628224076800. Its totient is φ = 53278310400.

The previous prime is 201221212193. The next prime is 201221212207. The reversal of 201221212200 is 2212122102.

It is an interprime number because it is at equal distance from previous prime (201221212193) and next prime (201221212207).

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 201221212200.

It is not an unprimeable number, because it can be changed into a prime (201221212207) 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, 77124496 + ... + 77127104.

It is an arithmetic number, because the mean of its divisors is an integer number (3272000400).

Almost surely, 2^201221212200 is an apocalyptic number.

201221212200 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 201221212200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (314112038400).

201221212200 is an abundant number, since it is smaller than the sum of its proper divisors (427002864600).

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

201221212200 is a wasteful number, since it uses less digits than its factorization.

201221212200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3492 (or 3483 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 201221212200 its reverse (2212122102), we get a palindrome (203433334302).

The spelling of 201221212200 in words is "two hundred one billion, two hundred twenty-one million, two hundred twelve thousand, two hundred".