689897 has 4 divisors (see below), whose sum is σ = 742980. Its totient is φ = 636816.

The previous prime is 689893. The next prime is 689903. The reversal of 689897 is 798986.

689897 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 798986 = 2 ⋅399493.

It can be written as a sum of positive squares in 2 ways, for example, as 440896 + 249001 = 664^2 + 499^2 .

It is a cyclic number.

It is not a de Polignac number, because 689897 - 2² = 689893 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (689891) 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, 26522 + ... + 26547.

It is an arithmetic number, because the mean of its divisors is an integer number (185745).

2⁶⁸⁹⁸⁹⁷ is an apocalyptic number.

It is an amenable number.

689897 is a deficient number, since it is larger than the sum of its proper divisors (53083).

689897 is a wasteful number, since it uses less digits than its factorization.

689897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53082.

The product of its digits is 217728, while the sum is 47.

The square root of 689897 is about 830.6003852636. The cubic root of 689897 is about 88.3611620716.

The spelling of 689897 in words is "six hundred eighty-nine thousand, eight hundred ninety-seven".