221100001200 has 360 divisors, whose sum is σ = 828391840640. Its totient is φ = 54286848000.

The previous prime is 221100001183. The next prime is 221100001207. The reversal of 221100001200 is 2100001122.

It is a tau number, because it is divible by the number of its divisors (360).

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

It is not an unprimeable number, because it can be changed into a prime (221100001207) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 19135425 + ... + 19146975.

Almost surely, 2^221100001200 is an apocalyptic number.

221100001200 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 221100001200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (414195920320).

221100001200 is an abundant number, since it is smaller than the sum of its proper divisors (607291839440).

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

221100001200 is a wasteful number, since it uses less digits than its factorization.

221100001200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11997 (or 11983 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 221100001200 its reverse (2100001122), we get a palindrome (223200002322).

The spelling of 221100001200 in words is "two hundred twenty-one billion, one hundred million, one thousand, two hundred".