665566 has 8 divisors (see below), whose sum is σ = 1089144. Its totient is φ = 302520.

The previous prime is 665563. The next prime is 665569.

665566 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (665563) and next prime (665569).

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15105 + ... + 15148.

It is an arithmetic number, because the mean of its divisors is an integer number (136143).

2⁶⁶⁵⁵⁶⁶ is an apocalyptic number.

665566 is a deficient number, since it is larger than the sum of its proper divisors (423578).

665566 is a wasteful number, since it uses less digits than its factorization.

665566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30266.

The product of its digits is 32400, while the sum is 34.

The square root of 665566 is about 815.8222845694. The cubic root of 665566 is about 87.3099439466.

The spelling of 665566 in words is "six hundred sixty-five thousand, five hundred sixty-six".