689659 has 4 divisors (see below), whose sum is σ = 691416. Its totient is φ = 687904.

The previous prime is 689641. The next prime is 689693. The reversal of 689659 is 956986.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 956986 = 2 ⋅478493.

It is a cyclic number.

It is not a de Polignac number, because 689659 - 2¹⁵ = 656891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (689629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12 + ... + 1174.

It is an arithmetic number, because the mean of its divisors is an integer number (172854).

2⁶⁸⁹⁶⁵⁹ is an apocalyptic number.

689659 is a deficient number, since it is larger than the sum of its proper divisors (1757).

689659 is a wasteful number, since it uses less digits than its factorization.

689659 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1756.

The product of its digits is 116640, while the sum is 43.

The square root of 689659 is about 830.4571030463. The cubic root of 689659 is about 88.3509999869.

The spelling of 689659 in words is "six hundred eighty-nine thousand, six hundred fifty-nine".