1221102221200 has 60 divisors (see below), whose sum is σ = 2981791557268. Its totient is φ = 480433651200.

The previous prime is 1221102221197. The next prime is 1221102221243. The reversal of 1221102221200 is 21222011221.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 264430435984 + 956671785216 = 514228^2 + 978096^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24998187 + ... + 25046986.

Almost surely, 2^{1221102221200} is an apocalyptic number.

1221102221200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221102221200 is an abundant number, since it is smaller than the sum of its proper divisors (1760689336068).

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

1221102221200 is a wasteful number, since it uses less digits than its factorization.

1221102221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50045252 (or 50045241 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1221102221200 its reverse (21222011221), we get a palindrome (1242324232421).

The spelling of 1221102221200 in words is "one trillion, two hundred twenty-one billion, one hundred two million, two hundred twenty-one thousand, two hundred".