669966 has 16 divisors (see below), whose sum is σ = 1461888. Its totient is φ = 203000.

The previous prime is 669947. The next prime is 669971.

669966 is nontrivially palindromic in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5010 + ... + 5141.

It is an arithmetic number, because the mean of its divisors is an integer number (91368).

2⁶⁶⁹⁹⁶⁶ is an apocalyptic number.

669966 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

669966 is an abundant number, since it is smaller than the sum of its proper divisors (791922).

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

669966 is a wasteful number, since it uses less digits than its factorization.

669966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10167.

The product of its digits is 104976, while the sum is 42.

The square root of 669966 is about 818.5145081182. The cubic root of 669966 is about 87.5019210463.

It can be divided in two parts, 66 and 9966, that multiplied together give a palindrome (657756).

The spelling of 669966 in words is "six hundred sixty-nine thousand, nine hundred sixty-six".