666005172 has 48 divisors (see below), whose sum is σ = 1785259392. Its totient is φ = 189296640.

The previous prime is 666005161. The next prime is 666005183. The reversal of 666005172 is 271500666.

It is an interprime number because it is at equal distance from previous prime (666005161) and next prime (666005183).

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 15 ways as a sum of consecutive naturals, for example, 4329 + ... + 36752.

It is an arithmetic number, because the mean of its divisors is an integer number (37192904).

Almost surely, 2^666005172 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666005172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (892629696).

666005172 is an abundant number, since it is smaller than the sum of its proper divisors (1119254220).

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

666005172 is a wasteful number, since it uses less digits than its factorization.

666005172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41288 (or 41286 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 33.

The square root of 666005172 is about 25807.0760063979. The cubic root of 666005172 is about 873.2914347101.

The spelling of 666005172 in words is "six hundred sixty-six million, five thousand, one hundred seventy-two".