121212331220 has 24 divisors (see below), whose sum is σ = 267943048800. Its totient is φ = 45933093792.

The previous prime is 121212331213. The next prime is 121212331223. The reversal of 121212331220 is 22133212121.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 121212331192 and 121212331201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121212331223) 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 7 ways as a sum of consecutive naturals, for example, 159489530 + ... + 159490289.

It is an arithmetic number, because the mean of its divisors is an integer number (11164293700).

Almost surely, 2^121212331220 is an apocalyptic number.

121212331220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121212331220 is an abundant number, since it is smaller than the sum of its proper divisors (146730717580).

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

121212331220 is a wasteful number, since it uses less digits than its factorization.

121212331220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318979847 (or 318979845 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 121212331220 its reverse (22133212121), we get a palindrome (143345543341).

The spelling of 121212331220 in words is "one hundred twenty-one billion, two hundred twelve million, three hundred thirty-one thousand, two hundred twenty".