689656417 has 2 divisors, whose sum is σ = 689656418. Its totient is φ = 689656416.

The previous prime is 689656361. The next prime is 689656463. The reversal of 689656417 is 714656986.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 689010001 + 646416 = 26249^2 + 804^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-689656417 is a prime.

It is not a weakly prime, because it can be changed into another prime (689656217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344828208 + 344828209.

It is an arithmetic number, because the mean of its divisors is an integer number (344828209).

Almost surely, 2^689656417 is an apocalyptic number.

It is an amenable number.

689656417 is a deficient number, since it is larger than the sum of its proper divisors (1).

689656417 is an equidigital number, since it uses as much as digits as its factorization.

689656417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2177280, while the sum is 52.

The square root of 689656417 is about 26261.3102681492. The cubic root of 689656417 is about 883.5088968554.

The spelling of 689656417 in words is "six hundred eighty-nine million, six hundred fifty-six thousand, four hundred seventeen".