666064 has 40 divisors (see below), whose sum is σ = 1557440. Its totient is φ = 269568.

The previous prime is 666041. The next prime is 666067. The reversal of 666064 is 460666.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666067) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1972 + ... + 2284.

It is an arithmetic number, because the mean of its divisors is an integer number (38936).

2⁶⁶⁶⁰⁶⁴ 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 666064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (778720).

666064 is an abundant number, since it is smaller than the sum of its proper divisors (891376).

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

666064 is a wasteful number, since it uses less digits than its factorization.

666064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347 (or 341 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 666064 is about 816.1274410287. The cubic root of 666064 is about 87.3317146460.

It can be divided in two parts, 6660 and 64, that added together give a square (6724 = 82²).

The spelling of 666064 in words is "six hundred sixty-six thousand, sixty-four".