687643285 has 16 divisors (see below), whose sum is σ = 998528256. Its totient is φ = 443789568.

The previous prime is 687643247. The next prime is 687643291. The reversal of 687643285 is 582346786.

It is a cyclic number.

It is not a de Polignac number, because 687643285 - 2⁹ = 687642773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 577257 + ... + 578446.

It is an arithmetic number, because the mean of its divisors is an integer number (62408016).

Almost surely, 2^687643285 is an apocalyptic number.

It is an amenable number.

687643285 is a deficient number, since it is larger than the sum of its proper divisors (310884971).

687643285 is a wasteful number, since it uses less digits than its factorization.

687643285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1155732.

The product of its digits is 1935360, while the sum is 49.

The square root of 687643285 is about 26222.9533996459. The cubic root of 687643285 is about 882.6483942344.

The spelling of 687643285 in words is "six hundred eighty-seven million, six hundred forty-three thousand, two hundred eighty-five".