21666871705222 has 4 divisors (see below), whose sum is σ = 32500307557836. Its totient is φ = 10833435852610.

The previous prime is 21666871705217. The next prime is 21666871705301. The reversal of 21666871705222 is 22250717866612.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5416717926304 + ... + 5416717926307.

It is an arithmetic number, because the mean of its divisors is an integer number (8125076889459).

Almost surely, 2^{21666871705222} is an apocalyptic number.

21666871705222 is a deficient number, since it is larger than the sum of its proper divisors (10833435852614).

21666871705222 is a wasteful number, since it uses less digits than its factorization.

21666871705222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10833435852613.

The product of its (nonzero) digits is 6773760, while the sum is 55.

The spelling of 21666871705222 in words is "twenty-one trillion, six hundred sixty-six billion, eight hundred seventy-one million, seven hundred five thousand, two hundred twenty-two".