121212222120 has 256 divisors, whose sum is σ = 445728096000. Its totient is φ = 29054361600.

The previous prime is 121212222119. The next prime is 121212222143. The reversal of 121212222120 is 21222212121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 121212222093 and 121212222102.

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, 1000000 + ... + 1114640.

It is an arithmetic number, because the mean of its divisors is an integer number (1741125375).

Almost surely, 2^121212222120 is an apocalyptic number.

121212222120 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 121212222120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222864048000).

121212222120 is an abundant number, since it is smaller than the sum of its proper divisors (324515873880).

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

121212222120 is a wasteful number, since it uses less digits than its factorization.

121212222120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114761 (or 114751 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 121212222120 its reverse (21222212121), we get a palindrome (142434434241).

Subtracting from 121212222120 its reverse (21222212121), we obtain a palindrome (99990009999).

The spelling of 121212222120 in words is "one hundred twenty-one billion, two hundred twelve million, two hundred twenty-two thousand, one hundred twenty".