689409 has 24 divisors (see below), whose sum is σ = 1178112. Its totient is φ = 380160.

The previous prime is 689393. The next prime is 689411. The reversal of 689409 is 904986.

It is not a de Polignac number, because 689409 - 2⁴ = 689393 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689459) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1777 + ... + 2129.

It is an arithmetic number, because the mean of its divisors is an integer number (49088).

2⁶⁸⁹⁴⁰⁹ is an apocalyptic number.

It is an amenable number.

689409 is a deficient number, since it is larger than the sum of its proper divisors (488703).

689409 is a wasteful number, since it uses less digits than its factorization.

689409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397 (or 394 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 689409 is about 830.3065698885. The cubic root of 689409 is about 88.3403230101.

The spelling of 689409 in words is "six hundred eighty-nine thousand, four hundred nine".