687069666 has 24 divisors (see below), whose sum is σ = 1489426380. Its totient is φ = 228903936.

The previous prime is 687069629. The next prime is 687069689. The reversal of 687069666 is 666960786.

It can be written as a sum of positive squares in 2 ways, for example, as 667964025 + 19105641 = 25845^2 + 4371^2 .

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 29890 + ... + 47618.

Almost surely, 2^687069666 is an apocalyptic number.

687069666 is an abundant number, since it is smaller than the sum of its proper divisors (802356714).

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

687069666 is a wasteful number, since it uses less digits than its factorization.

687069666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19890 (or 19887 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 54.

The square root of 687069666 is about 26212.0137723144. The cubic root of 687069666 is about 882.4028964360.

The spelling of 687069666 in words is "six hundred eighty-seven million, sixty-nine thousand, six hundred sixty-six".