686667866 has 16 divisors (see below), whose sum is σ = 1084934400. Its totient is φ = 325047168.

The previous prime is 686667853. The next prime is 686667869. The reversal of 686667866 is 668766686.

It is not an unprimeable number, because it can be changed into a prime (686667869) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61706 + ... + 71978.

It is an arithmetic number, because the mean of its divisors is an integer number (67808400).

Almost surely, 2^686667866 is an apocalyptic number.

686667866 is a deficient number, since it is larger than the sum of its proper divisors (398266534).

686667866 is a wasteful number, since it uses less digits than its factorization.

686667866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12053.

The product of its digits is 20901888, while the sum is 59.

The square root of 686667866 is about 26204.3482269642. The cubic root of 686667866 is about 882.2308524461.

The spelling of 686667866 in words is "six hundred eighty-six million, six hundred sixty-seven thousand, eight hundred sixty-six".