666072 has 72 divisors (see below), whose sum is σ = 2038140. Its totient is φ = 194880.

The previous prime is 666067. The next prime is 666073. The reversal of 666072 is 270666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666073) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 22954 + ... + 22982.

2⁶⁶⁶⁰⁷² 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 666072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1019070).

666072 is an abundant number, since it is smaller than the sum of its proper divisors (1372068).

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

666072 is a wasteful number, since it uses less digits than its factorization.

666072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81 (or 45 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 666072 is about 816.1323422093. The cubic root of 666072 is about 87.3320642876.

The spelling of 666072 in words is "six hundred sixty-six thousand, seventy-two".