It is a semiprime because it is the product of two primes.
It is a self number, because there is not a number n which added to its sum of digits gives 1213622.
It is a congruent number.
21213622 is an apocalyptic number.
1213622 is an equidigital number, since it uses as much as digits as its factorization.
1213622 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 606813.
The square root of 1213622 is about 1101.6451334255. The cubic root of 1213622 is about 106.6664431419. Note that the first 3 decimals are identical.
Adding to 1213622 its reverse (2263121), we get a palindrome (3476743).
The spelling of 1213622 in words is "one million, two hundred thirteen thousand, six hundred twenty-two".