669517 has 4 divisors (see below), whose sum is σ = 673180. Its totient is φ = 665856.

The previous prime is 669481. The next prime is 669527. The reversal of 669517 is 715966.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 715966 = 2 ⋅357983.

It can be written as a sum of positive squares in 2 ways, for example, as 75076 + 594441 = 274^2 + 771^2 .

It is a cyclic number.

It is not a de Polignac number, because 669517 - 2¹⁵ = 636749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1542 + ... + 1927.

It is an arithmetic number, because the mean of its divisors is an integer number (168295).

2⁶⁶⁹⁵¹⁷ is an apocalyptic number.

It is an amenable number.

669517 is a deficient number, since it is larger than the sum of its proper divisors (3663).

669517 is a wasteful number, since it uses less digits than its factorization.

669517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3662.

The product of its digits is 11340, while the sum is 34.

The square root of 669517 is about 818.2401847868. The cubic root of 669517 is about 87.4823692369.

The spelling of 669517 in words is "six hundred sixty-nine thousand, five hundred seventeen".