689407639 has 2 divisors, whose sum is σ = 689407640. Its totient is φ = 689407638.

The previous prime is 689407637. The next prime is 689407709. The reversal of 689407639 is 936704986.

689407639 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 689407639 - 2¹ = 689407637 is a prime.

Together with 689407637, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689407637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344703819 + 344703820.

It is an arithmetic number, because the mean of its divisors is an integer number (344703820).

Almost surely, 2^689407639 is an apocalyptic number.

689407639 is a deficient number, since it is larger than the sum of its proper divisors (1).

689407639 is an equidigital number, since it uses as much as digits as its factorization.

689407639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1959552, while the sum is 52.

The square root of 689407639 is about 26256.5732531875. The cubic root of 689407639 is about 883.4026487753.

The spelling of 689407639 in words is "six hundred eighty-nine million, four hundred seven thousand, six hundred thirty-nine".