1213121112 has 64 divisors (see below), whose sum is σ = 3469831680. Its totient is φ = 346228992.

The previous prime is 1213121099. The next prime is 1213121113. The reversal of 1213121112 is 2111213121.

It is a nude number because it is divisible by every one of its digits and also a Zuckerman number because it is divisible by the product of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 1213121091 and 1213121100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213121113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175188 + ... + 181980.

It is an arithmetic number, because the mean of its divisors is an integer number (54216120).

Almost surely, 2^1213121112 is an apocalyptic number.

1213121112 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1213121112 is an abundant number, since it is smaller than the sum of its proper divisors (2256710568).

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

1213121112 is a wasteful number, since it uses less digits than its factorization.

1213121112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7872 (or 7868 counting only the distinct ones).

The product of its digits is 24, while the sum is 15.

The square root of 1213121112 is about 34829.8881996483. Note that the first 3 decimals coincide. The cubic root of 1213121112 is about 1066.5176660797.

Adding to 1213121112 its reverse (2111213121), we get a palindrome (3324334233).

The spelling of 1213121112 in words is "one billion, two hundred thirteen million, one hundred twenty-one thousand, one hundred twelve".