669469 has 4 divisors (see below), whose sum is σ = 671580. Its totient is φ = 667360.

The previous prime is 669463. The next prime is 669479. The reversal of 669469 is 964966.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 964966 = 2 ⋅482483.

It can be written as a sum of positive squares in 2 ways, for example, as 324900 + 344569 = 570^2 + 587^2 .

It is a cyclic number.

It is not a de Polignac number, because 669469 - 2⁵ = 669437 is a prime.

It is a super-2 number, since 2×669469² = 896377483922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669463) 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, 472 + ... + 1249.

It is an arithmetic number, because the mean of its divisors is an integer number (167895).

2⁶⁶⁹⁴⁶⁹ is an apocalyptic number.

It is an amenable number.

669469 is a deficient number, since it is larger than the sum of its proper divisors (2111).

669469 is a wasteful number, since it uses less digits than its factorization.

669469 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2110.

The product of its digits is 69984, while the sum is 40.

The square root of 669469 is about 818.2108530202. The cubic root of 669469 is about 87.4802785486.

The spelling of 669469 in words is "six hundred sixty-nine thousand, four hundred sixty-nine".