686787556 has 96 divisors (see below), whose sum is σ = 1605042432. Its totient is φ = 249384960.

The previous prime is 686787533. The next prime is 686787559. The reversal of 686787556 is 655787686.

It is a self number, because there is not a number n which added to its sum of digits gives 686787556.

It is not an unprimeable number, because it can be changed into a prime (686787559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 252355 + ... + 255061.

It is an arithmetic number, because the mean of its divisors is an integer number (16719192).

Almost surely, 2^686787556 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686787556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (802521216).

686787556 is an abundant number, since it is smaller than the sum of its proper divisors (918254876).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

686787556 is a wasteful number, since it uses less digits than its factorization.

686787556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2789 (or 2787 counting only the distinct ones).

The product of its digits is 16934400, while the sum is 58.

The square root of 686787556 is about 26206.6319087364. The cubic root of 686787556 is about 882.2821087042.

The spelling of 686787556 in words is "six hundred eighty-six million, seven hundred eighty-seven thousand, five hundred fifty-six".