686673697 has 6 divisors (see below), whose sum is σ = 696307218. Its totient is φ = 677046384.

The previous prime is 686673643. The next prime is 686673721. The reversal of 686673697 is 796376686.

It can be written as a sum of positive squares in only one way, i.e., 602015296 + 84658401 = 24536^2 + 9201^2 .

It is a de Polignac number, because none of the positive numbers 2^k-686673697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (686673607) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 222358 + ... + 225424.

It is an arithmetic number, because the mean of its divisors is an integer number (116051203).

Almost surely, 2^686673697 is an apocalyptic number.

It is an amenable number.

686673697 is a deficient number, since it is larger than the sum of its proper divisors (9633521).

686673697 is an frugal number, since it uses more digits than its factorization.

686673697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6207 (or 3140 counting only the distinct ones).

The product of its digits is 13716864, while the sum is 58.

The square root of 686673697 is about 26204.4594868889. The cubic root of 686673697 is about 882.2333496619.

The spelling of 686673697 in words is "six hundred eighty-six million, six hundred seventy-three thousand, six hundred ninety-seven".