666687587 has 8 divisors (see below), whose sum is σ = 678320400. Its totient is φ = 655104384.

The previous prime is 666687569. The next prime is 666687607. The reversal of 666687587 is 785786666.

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 666687587 - 2⁸ = 666687331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666687517) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 15239 + ... + 39567.

It is an arithmetic number, because the mean of its divisors is an integer number (84790050).

Almost surely, 2^666687587 is an apocalyptic number.

666687587 is a gapful number since it is divisible by the number (67) formed by its first and last digit.

666687587 is a deficient number, since it is larger than the sum of its proper divisors (11632813).

666687587 is a wasteful number, since it uses less digits than its factorization.

666687587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24805.

The product of its digits is 20321280, while the sum is 59.

The square root of 666687587 is about 25820.2940920509. The cubic root of 666687587 is about 873.5896024380.

The spelling of 666687587 in words is "six hundred sixty-six million, six hundred eighty-seven thousand, five hundred eighty-seven".