666466 has 4 divisors (see below), whose sum is σ = 999702. Its totient is φ = 333232.

The previous prime is 666461. The next prime is 666467. The reversal of 666466 is 664666.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 450241 + 216225 = 671^2 + 465^2 .

It is not an unprimeable number, because it can be changed into a prime (666461) by changing a digit.

666466 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166615 + ... + 166618.

2⁶⁶⁶⁴⁶⁶ is an apocalyptic number.

666466 is a deficient number, since it is larger than the sum of its proper divisors (333236).

666466 is a wasteful number, since it uses less digits than its factorization.

666466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333235.

The product of its digits is 31104, while the sum is 34.

The square root of 666466 is about 816.3736889440. The cubic root of 666466 is about 87.3492806701.

The spelling of 666466 in words is "six hundred sixty-six thousand, four hundred sixty-six".