121212112121220 has 192 divisors, whose sum is σ = 355588247347200. Its totient is φ = 30809531450880.

The previous prime is 121212112121201. The next prime is 121212112121237. The reversal of 121212112121220 is 22121211212121.

It is a super-2 number, since 2×121212112121220² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1122581835 + ... + 1122689805.

It is an arithmetic number, because the mean of its divisors is an integer number (1852022121600).

Almost surely, 2^{121212112121220} is an apocalyptic number.

121212112121220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121212112121220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (177794123673600).

121212112121220 is an abundant number, since it is smaller than the sum of its proper divisors (234376135225980).

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

121212112121220 is a wasteful number, since it uses less digits than its factorization.

121212112121220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116258 (or 116256 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 121212112121220 its reverse (22121211212121), we get a palindrome (143333323333341).

Subtracting from 121212112121220 its reverse (22121211212121), we obtain a palindrome (99090900909099).

The spelling of 121212112121220 in words is "one hundred twenty-one trillion, two hundred twelve billion, one hundred twelve million, one hundred twenty-one thousand, two hundred twenty".