21222004636215 has 48 divisors (see below), whose sum is σ = 38949189552000. Its totient is φ = 10652458392576.

The previous prime is 21222004636213. The next prime is 21222004636253. The reversal of 21222004636215 is 51263640022212.

21222004636215 is a `hidden beast` number, since 2 + 1 + 2 + 2 + 2 + 0 + 0 + 4 + 636 + 2 + 15 = 666.

It is not a de Polignac number, because 21222004636215 - 2¹ = 21222004636213 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21222004636215.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222004636213) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 66509826 + ... + 66828144.

It is an arithmetic number, because the mean of its divisors is an integer number (811441449000).

Almost surely, 2^{21222004636215} is an apocalyptic number.

21222004636215 is a deficient number, since it is larger than the sum of its proper divisors (17727184915785).

21222004636215 is a wasteful number, since it uses less digits than its factorization.

21222004636215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405496 (or 405493 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

Adding to 21222004636215 its reverse (51263640022212), we get a palindrome (72485644658427).

The spelling of 21222004636215 in words is "twenty-one trillion, two hundred twenty-two billion, four million, six hundred thirty-six thousand, two hundred fifteen".