1221202201220 has 48 divisors (see below), whose sum is σ = 2566707916080. Its totient is φ = 488065222656.

The previous prime is 1221202201211. The next prime is 1221202201243. The reversal of 1221202201220 is 221022021221.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 295361814784 + 925840386436 = 543472^2 + 962206^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 201084104 + ... + 201090176.

It is an arithmetic number, because the mean of its divisors is an integer number (53473081585).

Almost surely, 2^{1221202201220} is an apocalyptic number.

1221202201220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221202201220 is an abundant number, since it is smaller than the sum of its proper divisors (1345505714860).

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

1221202201220 is a wasteful number, since it uses less digits than its factorization.

1221202201220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12984 (or 12982 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 1221202201220 its reverse (221022021221), we get a palindrome (1442224222441).

The spelling of 1221202201220 in words is "one trillion, two hundred twenty-one billion, two hundred two million, two hundred one thousand, two hundred twenty".