669638 has 8 divisors (see below), whose sum is σ = 1013688. Its totient is φ = 331744.

The previous prime is 669637. The next prime is 669649. The reversal of 669638 is 836966.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669637) 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, 1256 + ... + 1707.

It is an arithmetic number, because the mean of its divisors is an integer number (126711).

2⁶⁶⁹⁶³⁸ is an apocalyptic number.

669638 is a deficient number, since it is larger than the sum of its proper divisors (344050).

669638 is a wasteful number, since it uses less digits than its factorization.

669638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3078.

The product of its digits is 46656, while the sum is 38.

The square root of 669638 is about 818.3141206163. The cubic root of 669638 is about 87.4876390702.

The spelling of 669638 in words is "six hundred sixty-nine thousand, six hundred thirty-eight".