689779 has 2 divisors, whose sum is σ = 689780. Its totient is φ = 689778.

The previous prime is 689771. The next prime is 689789. The reversal of 689779 is 977986.

689779 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 689779 - 2³ = 689771 is a prime.

It is not a weakly prime, because it can be changed into another prime (689771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344889 + 344890.

It is an arithmetic number, because the mean of its divisors is an integer number (344890).

2⁶⁸⁹⁷⁷⁹ is an apocalyptic number.

689779 is a deficient number, since it is larger than the sum of its proper divisors (1).

689779 is an equidigital number, since it uses as much as digits as its factorization.

689779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 190512, while the sum is 46.

The square root of 689779 is about 830.5293492707. The cubic root of 689779 is about 88.3561240192.

It can be divided in two parts, 68977 and 9, that added together give a palindrome (68986).

The spelling of 689779 in words is "six hundred eighty-nine thousand, seven hundred seventy-nine".