686866577 has 2 divisors, whose sum is σ = 686866578. Its totient is φ = 686866576.

The previous prime is 686866547. The next prime is 686866619. The reversal of 686866577 is 775668686.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 450967696 + 235898881 = 21236^2 + 15359^2 .

It is a cyclic number.

It is not a de Polignac number, because 686866577 - 2¹⁴ = 686850193 is a prime.

It is not a weakly prime, because it can be changed into another prime (686866517) 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, 343433288 + 343433289.

It is an arithmetic number, because the mean of its divisors is an integer number (343433289).

Almost surely, 2^686866577 is an apocalyptic number.

It is an amenable number.

686866577 is a deficient number, since it is larger than the sum of its proper divisors (1).

686866577 is an equidigital number, since it uses as much as digits as its factorization.

686866577 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20321280, while the sum is 59.

The square root of 686866577 is about 26208.1395180963. The cubic root of 686866577 is about 882.3159455339.

The spelling of 686866577 in words is "six hundred eighty-six million, eight hundred sixty-six thousand, five hundred seventy-seven".