121212120 has 128 divisors (see below), whose sum is σ = 374984640. Its totient is φ = 31334400.

The previous prime is 121212103. The next prime is 121212127. The reversal of 121212120 is 21212121.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 121212096 and 121212105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121212127) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 884692 + ... + 884828.

Almost surely, 2^121212120 is an apocalyptic number.

121212120 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 121212120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187492320).

121212120 is an abundant number, since it is smaller than the sum of its proper divisors (253772520).

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

121212120 is a wasteful number, since it uses less digits than its factorization.

121212120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325 (or 321 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 121212120 is about 11009.6375962154. The cubic root of 121212120 is about 494.8976015103.

Adding to 121212120 its reverse (21212121), we get a palindrome (142424241).

Subtracting from 121212120 its reverse (21212121), we obtain a palindrome (99999999).

It can be divided in two parts, 12121 and 2120, that added together give a palindrome (14241).

The spelling of 121212120 in words is "one hundred twenty-one million, two hundred twelve thousand, one hundred twenty".