687866091 has 16 divisors (see below), whose sum is σ = 1010851968. Its totient is φ = 412588800.

The previous prime is 687866077. The next prime is 687866107. The reversal of 687866091 is 190668786.

It is a happy number.

It is not a de Polignac number, because 687866091 - 2⁵ = 687866059 is a prime.

It is not an unprimeable number, because it can be changed into a prime (687866041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104245 + ... + 110646.

It is an arithmetic number, because the mean of its divisors is an integer number (63178248).

Almost surely, 2^687866091 is an apocalyptic number.

687866091 is a deficient number, since it is larger than the sum of its proper divisors (322985877).

687866091 is a wasteful number, since it uses less digits than its factorization.

687866091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215002.

The product of its (nonzero) digits is 870912, while the sum is 51.

The square root of 687866091 is about 26227.2013566068. The cubic root of 687866091 is about 882.7437140637.

The spelling of 687866091 in words is "six hundred eighty-seven million, eight hundred sixty-six thousand, ninety-one".