687903985 has 16 divisors (see below), whose sum is σ = 844588800. Its totient is φ = 537630336.

The previous prime is 687903977. The next prime is 687903991. The reversal of 687903985 is 589309786.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 687903985 - 2³ = 687903977 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 143101 + ... + 147829.

It is an arithmetic number, because the mean of its divisors is an integer number (52786800).

Almost surely, 2^687903985 is an apocalyptic number.

It is an amenable number.

687903985 is a deficient number, since it is larger than the sum of its proper divisors (156684815).

687903985 is a wasteful number, since it uses less digits than its factorization.

687903985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5400.

The product of its (nonzero) digits is 3265920, while the sum is 55.

The square root of 687903985 is about 26227.9237645682. The cubic root of 687903985 is about 882.7599236509.

The spelling of 687903985 in words is "six hundred eighty-seven million, nine hundred three thousand, nine hundred eighty-five".