221212231312 has 40 divisors (see below), whose sum is σ = 433454991480. Its totient is φ = 109355980800.

The previous prime is 221212231309. The next prime is 221212231313. The reversal of 221212231312 is 213132212122.

It can be written as a sum of positive squares in 4 ways, for example, as 11598428416 + 209613802896 = 107696^2 + 457836^2 .

It is not an unprimeable number, because it can be changed into a prime (221212231313) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1049208 + ... + 1242280.

It is an arithmetic number, because the mean of its divisors is an integer number (10836374787).

Almost surely, 2^221212231312 is an apocalyptic number.

It is an amenable number.

221212231312 is a deficient number, since it is larger than the sum of its proper divisors (212242760168).

221212231312 is a wasteful number, since it uses less digits than its factorization.

221212231312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193891 (or 193885 counting only the distinct ones).

The product of its digits is 576, while the sum is 22.

Adding to 221212231312 its reverse (213132212122), we get a palindrome (434344443434).

The spelling of 221212231312 in words is "two hundred twenty-one billion, two hundred twelve million, two hundred thirty-one thousand, three hundred twelve".