1221200012120 has 64 divisors (see below), whose sum is σ = 2998604448000. Its totient is φ = 443907767680.

The previous prime is 1221200012119. The next prime is 1221200012143. The reversal of 1221200012120 is 212100021221.

It is a junction number, because it is equal to n+sod(n) for n = 1221200012095 and 1221200012104.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 673397 + ... + 1701723.

It is an arithmetic number, because the mean of its divisors is an integer number (46853194500).

Almost surely, 2^{1221200012120} is an apocalyptic number.

1221200012120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221200012120 is an abundant number, since it is smaller than the sum of its proper divisors (1777404435880).

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

1221200012120 is a wasteful number, since it uses less digits than its factorization.

1221200012120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1031048 (or 1031044 counting only the distinct ones).

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

Adding to 1221200012120 its reverse (212100021221), we get a palindrome (1433300033341).

The spelling of 1221200012120 in words is "one trillion, two hundred twenty-one billion, two hundred million, twelve thousand, one hundred twenty".