689408 has 18 divisors (see below), whose sum is σ = 1376634. Its totient is φ = 344576.

The previous prime is 689393. The next prime is 689411. The reversal of 689408 is 804986.

It can be written as a sum of positive squares in only one way, i.e., 565504 + 123904 = 752^2 + 352^2 .

It is a nialpdrome in base 16.

It is a congruent number.

It is an unprimeable number.

689408 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1091 + ... + 1602.

2⁶⁸⁹⁴⁰⁸ is an apocalyptic number.

It is an amenable number.

689408 is a deficient number, since it is larger than the sum of its proper divisors (687226).

689408 is an equidigital number, since it uses as much as digits as its factorization.

689408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2709 (or 2695 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 689408 is about 830.3059677011. The cubic root of 689408 is about 88.3402802970.

The spelling of 689408 in words is "six hundred eighty-nine thousand, four hundred eight".