1221202012120 has 32 divisors (see below), whose sum is σ = 2753440905600. Its totient is φ = 487461004288.

The previous prime is 1221202012117. The next prime is 1221202012127. The reversal of 1221202012120 is 212102021221.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1221202012094 and 1221202012103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221202012127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31849369 + ... + 31887688.

It is an arithmetic number, because the mean of its divisors is an integer number (86045028300).

Almost surely, 2^{1221202012120} is an apocalyptic number.

1221202012120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221202012120 is an abundant number, since it is smaller than the sum of its proper divisors (1532238893480).

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

1221202012120 is a wasteful number, since it uses less digits than its factorization.

1221202012120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63737547 (or 63737543 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1221202012120 its reverse (212102021221), we get a palindrome (1433304033341).

The spelling of 1221202012120 in words is "one trillion, two hundred twenty-one billion, two hundred two million, twelve thousand, one hundred twenty".