686331992 has 8 divisors (see below), whose sum is σ = 1286872500. Its totient is φ = 343165992.

The previous prime is 686331991. The next prime is 686332061. The reversal of 686331992 is 299133686.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686331991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42895742 + ... + 42895757.

Almost surely, 2^686331992 is an apocalyptic number.

It is an amenable number.

686331992 is a deficient number, since it is larger than the sum of its proper divisors (600540508).

686331992 is a wasteful number, since it uses less digits than its factorization.

686331992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85791505 (or 85791501 counting only the distinct ones).

The product of its digits is 419904, while the sum is 47.

The square root of 686331992 is about 26197.9386975388. The cubic root of 686331992 is about 882.0869853518.

The spelling of 686331992 in words is "six hundred eighty-six million, three hundred thirty-one thousand, nine hundred ninety-two".