121220128 has 24 divisors (see below), whose sum is σ = 241678080. Its totient is φ = 59841600.

The previous prime is 121220117. The next prime is 121220147. The reversal of 121220128 is 821022121.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21448 + ... + 26503.

It is an arithmetic number, because the mean of its divisors is an integer number (10069920).

Almost surely, 2^121220128 is an apocalyptic number.

It is an amenable number.

121220128 is a deficient number, since it is larger than the sum of its proper divisors (120457952).

121220128 is an equidigital number, since it uses as much as digits as its factorization.

121220128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48040 (or 48032 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 121220128 is about 11010.0012715712. The cubic root of 121220128 is about 494.9084999054.

Adding to 121220128 its reverse (821022121), we get a palindrome (942242249).

The spelling of 121220128 in words is "one hundred twenty-one million, two hundred twenty thousand, one hundred twenty-eight".