221121001200 has 240 divisors, whose sum is σ = 773307505152. Its totient is φ = 53564160000.

The previous prime is 221121001193. The next prime is 221121001237. The reversal of 221121001200 is 2100121122.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 19543545 + ... + 19554855.

Almost surely, 2^221121001200 is an apocalyptic number.

221121001200 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 221121001200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (386653752576).

221121001200 is an abundant number, since it is smaller than the sum of its proper divisors (552186503952).

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

221121001200 is a wasteful number, since it uses less digits than its factorization.

221121001200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12824 (or 12813 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 221121001200 its reverse (2100121122), we get a palindrome (223221122322).

The spelling of 221121001200 in words is "two hundred twenty-one billion, one hundred twenty-one million, one thousand, two hundred".