121220221020 has 48 divisors (see below), whose sum is σ = 339827177088. Its totient is φ = 32286291520.

The previous prime is 121220220991. The next prime is 121220221021. The reversal of 121220221020 is 20122022121.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121220221021) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 1171866 + ... + 1271105.

It is an arithmetic number, because the mean of its divisors is an integer number (7079732856).

Almost surely, 2^121220221020 is an apocalyptic number.

121220221020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121220221020 is an abundant number, since it is smaller than the sum of its proper divisors (218606956068).

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

121220221020 is a wasteful number, since it uses less digits than its factorization.

121220221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2443810 (or 2443808 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 121220221020 its reverse (20122022121), we get a palindrome (141342243141).

The spelling of 121220221020 in words is "one hundred twenty-one billion, two hundred twenty million, two hundred twenty-one thousand, twenty".