686658601 has 2 divisors, whose sum is σ = 686658602. Its totient is φ = 686658600.

The previous prime is 686658593. The next prime is 686658631. The reversal of 686658601 is 106856686.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 393427225 + 293231376 = 19835^2 + 17124^2 .

It is a cyclic number.

It is not a de Polignac number, because 686658601 - 2³ = 686658593 is a prime.

It is not a weakly prime, because it can be changed into another prime (686658631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343329300 + 343329301.

It is an arithmetic number, because the mean of its divisors is an integer number (343329301).

Almost surely, 2^686658601 is an apocalyptic number.

It is an amenable number.

686658601 is a deficient number, since it is larger than the sum of its proper divisors (1).

686658601 is an equidigital number, since it uses as much as digits as its factorization.

686658601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 414720, while the sum is 46.

The square root of 686658601 is about 26204.1714427303. The cubic root of 686658601 is about 882.2268845377.

The spelling of 686658601 in words is "six hundred eighty-six million, six hundred fifty-eight thousand, six hundred one".