1201222221100 has 144 divisors (see below), whose sum is σ = 2949898694400. Its totient is φ = 420566944000.

The previous prime is 1201222221053. The next prime is 1201222221161. The reversal of 1201222221100 is 11222221021.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11399655 + ... + 11504545.

It is an arithmetic number, because the mean of its divisors is an integer number (20485407600).

Almost surely, 2^{1201222221100} is an apocalyptic number.

1201222221100 is a gapful number since it is divisible by the number (10) 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 1201222221100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1474949347200).

1201222221100 is an abundant number, since it is smaller than the sum of its proper divisors (1748676473300).

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

1201222221100 is a wasteful number, since it uses less digits than its factorization.

1201222221100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105304 (or 105297 counting only the distinct ones).

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

Adding to 1201222221100 its reverse (11222221021), we get a palindrome (1212444442121).

The spelling of 1201222221100 in words is "one trillion, two hundred one billion, two hundred twenty-two million, two hundred twenty-one thousand, one hundred".