689734169 has 2 divisors, whose sum is σ = 689734170. Its totient is φ = 689734168.

The previous prime is 689734139. The next prime is 689734207. The reversal of 689734169 is 961437986.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 449948944 + 239785225 = 21212^2 + 15485^2 .

It is a cyclic number.

It is not a de Polignac number, because 689734169 - 2¹² = 689730073 is a prime.

It is a super-2 number, since 2×689734169² = 951466447772241122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 689734169.

It is not a weakly prime, because it can be changed into another prime (689734139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344867084 + 344867085.

It is an arithmetic number, because the mean of its divisors is an integer number (344867085).

Almost surely, 2^689734169 is an apocalyptic number.

It is an amenable number.

689734169 is a deficient number, since it is larger than the sum of its proper divisors (1).

689734169 is an equidigital number, since it uses as much as digits as its factorization.

689734169 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1959552, while the sum is 53.

The square root of 689734169 is about 26262.7905790683. The cubic root of 689734169 is about 883.5420979299.

The spelling of 689734169 in words is "six hundred eighty-nine million, seven hundred thirty-four thousand, one hundred sixty-nine".