669545 has 8 divisors (see below), whose sum is σ = 850824. Its totient is φ = 504064.

The previous prime is 669527. The next prime is 669551. The reversal of 669545 is 545966.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 50176 + 619369 = 224^2 + 787^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 669545 - 2⁶ = 669481 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 3854 + ... + 4023.

It is an arithmetic number, because the mean of its divisors is an integer number (106353).

2⁶⁶⁹⁵⁴⁵ is an apocalyptic number.

It is an amenable number.

669545 is a deficient number, since it is larger than the sum of its proper divisors (181279).

669545 is a wasteful number, since it uses less digits than its factorization.

669545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7899.

The product of its digits is 32400, while the sum is 35.

The square root of 669545 is about 818.2572944985. The cubic root of 669545 is about 87.4835887589.

The spelling of 669545 in words is "six hundred sixty-nine thousand, five hundred forty-five".