1221021002120 has 32 divisors (see below), whose sum is σ = 2747350206720. Its totient is φ = 488398987200.

The previous prime is 1221021002119. The next prime is 1221021002143. The reversal of 1221021002120 is 212001201221.

It is a junction number, because it is equal to n+sod(n) for n = 1221021002095 and 1221021002104.

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, 2034695 + ... + 2565545.

It is an arithmetic number, because the mean of its divisors is an integer number (85854693960).

Almost surely, 2^{1221021002120} is an apocalyptic number.

1221021002120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221021002120 is an abundant number, since it is smaller than the sum of its proper divisors (1526329204600).

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

1221021002120 is a wasteful number, since it uses less digits than its factorization.

1221021002120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 588365 (or 588361 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 1221021002120 its reverse (212001201221), we get a palindrome (1433022203341).

The spelling of 1221021002120 in words is "one trillion, two hundred twenty-one billion, twenty-one million, two thousand, one hundred twenty".