669866 has 8 divisors (see below), whose sum is σ = 1020000. Its totient is φ = 329868.

The previous prime is 669863. The next prime is 669869. The reversal of 669866 is 668966.

It is an interprime number because it is at equal distance from previous prime (669863) and next prime (669869).

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

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 669866.

It is not an unprimeable number, because it can be changed into a prime (669863) 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, 2366 + ... + 2633.

It is an arithmetic number, because the mean of its divisors is an integer number (127500).

2⁶⁶⁹⁸⁶⁶ is an apocalyptic number.

669866 is a deficient number, since it is larger than the sum of its proper divisors (350134).

669866 is a wasteful number, since it uses less digits than its factorization.

669866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5068.

The product of its digits is 93312, while the sum is 41.

The square root of 669866 is about 818.4534195664. The cubic root of 669866 is about 87.4975672793.

Subtracting from 669866 its reverse (668966), we obtain a square (900 = 30²).

It can be divided in two parts, 66 and 9866, that multiplied together give a palindrome (651156).

The spelling of 669866 in words is "six hundred sixty-nine thousand, eight hundred sixty-six".