20172170165506 has 8 divisors (see below), whose sum is σ = 30258359400204. Its totient is φ = 10086050365440.

The previous prime is 20172170165473. The next prime is 20172170165513. The reversal of 20172170165506 is 60556107127102.

It can be written as a sum of positive squares in 2 ways, for example, as 19787595305625 + 384574859881 = 4448325^2 + 620141^2 .

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

It is a super-2 number, since 2×20172170165506² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16626175 + ... + 17798146.

Almost surely, 2^{20172170165506} is an apocalyptic number.

20172170165506 is a deficient number, since it is larger than the sum of its proper divisors (10086189234698).

20172170165506 is a wasteful number, since it uses less digits than its factorization.

20172170165506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34717316.

The product of its (nonzero) digits is 176400, while the sum is 43.

The spelling of 20172170165506 in words is "twenty trillion, one hundred seventy-two billion, one hundred seventy million, one hundred sixty-five thousand, five hundred six".