8172191705 has 8 divisors (see below), whose sum is σ = 9807217992. Its totient is φ = 6537361408.

The previous prime is 8172191681. The next prime is 8172191747. The reversal of 8172191705 is 5071912718.

It can be written as a sum of positive squares in 4 ways, for example, as 1420611481 + 6751580224 = 37691^2 + 82168^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 8172191705 - 2⁶ = 8172191641 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68249 + ... + 144921.

It is an arithmetic number, because the mean of its divisors is an integer number (1225902249).

Almost surely, 2^8172191705 is an apocalyptic number.

It is an amenable number.

8172191705 is a deficient number, since it is larger than the sum of its proper divisors (1635026287).

8172191705 is a wasteful number, since it uses less digits than its factorization.

8172191705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97995.

The product of its (nonzero) digits is 35280, while the sum is 41.

The square root of 8172191705 is about 90400.1753593432. The cubic root of 8172191705 is about 2014.2475710955.

The spelling of 8172191705 in words is "eight billion, one hundred seventy-two million, one hundred ninety-one thousand, seven hundred five".