21705172022 has 8 divisors (see below), whose sum is σ = 32576659176. Its totient is φ = 10846285632.

The previous prime is 21705172019. The next prime is 21705172033. The reversal of 21705172022 is 22027150712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21705172022² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3145883 + ... + 3152774.

It is an arithmetic number, because the mean of its divisors is an integer number (4072082397).

Almost surely, 2^21705172022 is an apocalyptic number.

21705172022 is a deficient number, since it is larger than the sum of its proper divisors (10871487154).

21705172022 is a wasteful number, since it uses less digits than its factorization.

21705172022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6300382.

The product of its (nonzero) digits is 3920, while the sum is 29.

The spelling of 21705172022 in words is "twenty-one billion, seven hundred five million, one hundred seventy-two thousand, twenty-two".