689866637 has 2 divisors, whose sum is σ = 689866638. Its totient is φ = 689866636.

The previous prime is 689866627. The next prime is 689866657. The reversal of 689866637 is 736668986.

689866637 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 can be written as a sum of positive squares in only one way, i.e., 492351721 + 197514916 = 22189^2 + 14054^2 .

It is a cyclic number.

It is not a de Polignac number, because 689866637 - 2⁸ = 689866381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689866627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344933318 + 344933319.

It is an arithmetic number, because the mean of its divisors is an integer number (344933319).

Almost surely, 2^689866637 is an apocalyptic number.

It is an amenable number.

689866637 is a deficient number, since it is larger than the sum of its proper divisors (1).

689866637 is an equidigital number, since it uses as much as digits as its factorization.

689866637 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15676416, while the sum is 59.

The square root of 689866637 is about 26265.3124291336. The cubic root of 689866637 is about 883.5986576732.

The spelling of 689866637 in words is "six hundred eighty-nine million, eight hundred sixty-six thousand, six hundred thirty-seven".