21216224022066 has 12 divisors (see below), whose sum is σ = 45968485381182. Its totient is φ = 7072074674016.

The previous prime is 21216224021989. The next prime is 21216224022137. The reversal of 21216224022066 is 66022042261212.

21216224022066 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 622 + 4 + 0 + 2 + 20 + 6 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 11436375096441 + 9779848925625 = 3381771^2 + 3127275^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21216224022066.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 589339556151 + ... + 589339556186.

Almost surely, 2^{21216224022066} is an apocalyptic number.

21216224022066 is an abundant number, since it is smaller than the sum of its proper divisors (24752261359116).

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

21216224022066 is a wasteful number, since it uses less digits than its factorization.

21216224022066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178679112345 (or 1178679112342 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

Adding to 21216224022066 its reverse (66022042261212), we get a palindrome (87238266283278).

The spelling of 21216224022066 in words is "twenty-one trillion, two hundred sixteen billion, two hundred twenty-four million, twenty-two thousand, sixty-six".