21222015604164 has 84 divisors (see below), whose sum is σ = 55683714683184. Its totient is φ = 7073827857072.

The previous prime is 21222015604147. The next prime is 21222015604169. The reversal of 21222015604164 is 46140651022212.

21222015604164 is a `hidden beast` number, since 2 + 1 + 2 + 2 + 20 + 15 + 604 + 16 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21222015604169) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 171711039 + ... + 171834585.

It is an arithmetic number, because the mean of its divisors is an integer number (662901365276).

Almost surely, 2^{21222015604164} is an apocalyptic number.

It is an amenable number.

21222015604164 is an abundant number, since it is smaller than the sum of its proper divisors (34461699079020).

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

21222015604164 is a wasteful number, since it uses less digits than its factorization.

21222015604164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182476 (or 182459 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

Adding to 21222015604164 its reverse (46140651022212), we get a palindrome (67362666626376).

The spelling of 21222015604164 in words is "twenty-one trillion, two hundred twenty-two billion, fifteen million, six hundred four thousand, one hundred sixty-four".