687649903 has 8 divisors (see below), whose sum is σ = 702671040. Its totient is φ = 672645120.

The previous prime is 687649849. The next prime is 687649913. The reversal of 687649903 is 309946786.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 687649903 - 2²⁵ = 654095471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687649913) 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, 123663 + ... + 129103.

It is an arithmetic number, because the mean of its divisors is an integer number (87833880).

Almost surely, 2^687649903 is an apocalyptic number.

687649903 is a deficient number, since it is larger than the sum of its proper divisors (15021137).

687649903 is a wasteful number, since it uses less digits than its factorization.

687649903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8177.

The product of its (nonzero) digits is 1959552, while the sum is 52.

The square root of 687649903 is about 26223.0795865017. The cubic root of 687649903 is about 882.6512258131.

The spelling of 687649903 in words is "six hundred eighty-seven million, six hundred forty-nine thousand, nine hundred three".