1211121212 has 48 divisors (see below), whose sum is σ = 2565373440. Its totient is φ = 489056832.

The previous prime is 1211121209. The next prime is 1211121227. The reversal of 1211121212 is 2121211121.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29114 + ... + 57182.

It is an arithmetic number, because the mean of its divisors is an integer number (53445280).

Almost surely, 2^1211121212 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1211121212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1282686720).

1211121212 is an abundant number, since it is smaller than the sum of its proper divisors (1354252228).

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

1211121212 is a wasteful number, since it uses less digits than its factorization.

1211121212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28170 (or 28168 counting only the distinct ones).

The product of its digits is 16, while the sum is 14.

The square root of 1211121212 is about 34801.1668195191. The cubic root of 1211121212 is about 1065.9312718005.

Adding to 1211121212 its reverse (2121211121), we get a palindrome (3332332333).

It can be divided in two parts, 1211121 and 212, that multiplied together give a palindrome (256757652).

The spelling of 1211121212 in words is "one billion, two hundred eleven million, one hundred twenty-one thousand, two hundred twelve".