1221002313220 has 24 divisors (see below), whose sum is σ = 2568548737944. Its totient is φ = 487554471936.

The previous prime is 1221002313173. The next prime is 1221002313233. The reversal of 1221002313220 is 223132001221.

It can be written as a sum of positive squares in 4 ways, for example, as 662228123076 + 558774190144 = 813774^2 + 747512^2 .

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 7 ways as a sum of consecutive naturals, for example, 52891507 + ... + 52914586.

It is an arithmetic number, because the mean of its divisors is an integer number (107022864081).

Almost surely, 2^{1221002313220} is an apocalyptic number.

1221002313220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221002313220 is an abundant number, since it is smaller than the sum of its proper divisors (1347546424724).

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

1221002313220 is a wasteful number, since it uses less digits than its factorization.

1221002313220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105806679 (or 105806677 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 1221002313220 its reverse (223132001221), we get a palindrome (1444134314441).

The spelling of 1221002313220 in words is "one trillion, two hundred twenty-one billion, two million, three hundred thirteen thousand, two hundred twenty".