1221002110120 has 64 divisors (see below), whose sum is σ = 2958826767120. Its totient is φ = 450794256384.

The previous prime is 1221002110099. The next prime is 1221002110169. The reversal of 1221002110120 is 210112001221.

It can be written as a sum of positive squares in 8 ways, for example, as 49148229636 + 1171853880484 = 221694^2 + 1082522^2 .

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a self number, because there is not a number n which added to its sum of digits gives 1221002110120.

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, 6644922 + ... + 6826198.

Almost surely, 2^{1221002110120} is an apocalyptic number.

1221002110120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221002110120 is an abundant number, since it is smaller than the sum of its proper divisors (1737824657000).

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

1221002110120 is a wasteful number, since it uses less digits than its factorization.

1221002110120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194254 (or 194250 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1221002110120 its reverse (210112001221), we get a palindrome (1431114111341).

The spelling of 1221002110120 in words is "one trillion, two hundred twenty-one billion, two million, one hundred ten thousand, one hundred twenty".