121000021220 has 24 divisors (see below), whose sum is σ = 273646202424. Its totient is φ = 44676930816.

The previous prime is 121000021213. The next prime is 121000021237. The reversal of 121000021220 is 22120000121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 7468762084 + 113531259136 = 86422^2 + 336944^2 .

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, 232692089 + ... + 232692608.

It is an arithmetic number, because the mean of its divisors is an integer number (11401925101).

Almost surely, 2^121000021220 is an apocalyptic number.

121000021220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121000021220 is an abundant number, since it is smaller than the sum of its proper divisors (152646181204).

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

121000021220 is a wasteful number, since it uses less digits than its factorization.

121000021220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 465384719 (or 465384717 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 121000021220 its reverse (22120000121), we get a palindrome (143120021341).

The spelling of 121000021220 in words is "one hundred twenty-one billion, twenty-one thousand, two hundred twenty".