1211212220212 has 12 divisors (see below), whose sum is σ = 2192711778180. Its totient is φ = 584723140736.

The previous prime is 1211212220209. The next prime is 1211212220219. The reversal of 1211212220212 is 2120222121121.

It can be written as a sum of positive squares in 2 ways, for example, as 709897242916 + 501314977296 = 842554^2 + 708036^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1211212220212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211212220219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5220742213 + ... + 5220742444.

It is an arithmetic number, because the mean of its divisors is an integer number (182725981515).

Almost surely, 2^{1211212220212} is an apocalyptic number.

It is an amenable number.

1211212220212 is a deficient number, since it is larger than the sum of its proper divisors (981499557968).

1211212220212 is a wasteful number, since it uses less digits than its factorization.

1211212220212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10441484690 (or 10441484688 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 1211212220212 its reverse (2120222121121), we get a palindrome (3331434341333).

Subtracting 1211212220212 from its reverse (2120222121121), we obtain a palindrome (909009900909).

The spelling of 1211212220212 in words is "one trillion, two hundred eleven billion, two hundred twelve million, two hundred twenty thousand, two hundred twelve".