121221211220 has 12 divisors (see below), whose sum is σ = 254564543604. Its totient is φ = 48488484480.

The previous prime is 121221211159. The next prime is 121221211249. The reversal of 121221211220 is 22112122121.

It can be written as a sum of positive squares in 2 ways, for example, as 31626354244 + 89594856976 = 177838^2 + 299324^2 .

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 3030530261 + ... + 3030530300.

It is an arithmetic number, because the mean of its divisors is an integer number (21213711967).

Almost surely, 2^121221211220 is an apocalyptic number.

121221211220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121221211220 is an abundant number, since it is smaller than the sum of its proper divisors (133343332384).

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

121221211220 is a wasteful number, since it uses less digits than its factorization.

121221211220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6061060570 (or 6061060568 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 121221211220 its reverse (22112122121), we get a palindrome (143333333341).

The spelling of 121221211220 in words is "one hundred twenty-one billion, two hundred twenty-one million, two hundred eleven thousand, two hundred twenty".