665171173722 has 128 divisors (see below), whose sum is σ = 1538362368000. Its totient is φ = 189755375040.

The previous prime is 665171173721. The next prime is 665171173759. The reversal of 665171173722 is 227371171566.

It is not an unprimeable number, because it can be changed into a prime (665171173721) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 152455113 + ... + 152459475.

It is an arithmetic number, because the mean of its divisors is an integer number (12018456000).

Almost surely, 2^665171173722 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665171173722, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (769181184000).

665171173722 is an abundant number, since it is smaller than the sum of its proper divisors (873191194278).

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

665171173722 is a wasteful number, since it uses less digits than its factorization.

665171173722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5968.

The product of its digits is 740880, while the sum is 48.

The spelling of 665171173722 in words is "six hundred sixty-five billion, one hundred seventy-one million, one hundred seventy-three thousand, seven hundred twenty-two".