1221310201220 has 24 divisors (see below), whose sum is σ = 2565149391000. Its totient is φ = 488448276992.

The previous prime is 1221310201219. The next prime is 1221310201271. The reversal of 1221310201220 is 221020131221.

It can be written as a sum of positive squares in 4 ways, for example, as 794775816004 + 426534385216 = 891502^2 + 653096^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4605515 + ... + 4863474.

It is an arithmetic number, because the mean of its divisors is an integer number (106881224625).

Almost surely, 2^{1221310201220} is an apocalyptic number.

1221310201220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221310201220 is an abundant number, since it is smaller than the sum of its proper divisors (1343839189780).

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

1221310201220 is a wasteful number, since it uses less digits than its factorization.

1221310201220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9475447 (or 9475445 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 1221310201220 its reverse (221020131221), we get a palindrome (1442330332441).

The spelling of 1221310201220 in words is "one trillion, two hundred twenty-one billion, three hundred ten million, two hundred one thousand, two hundred twenty".