6646993587 has 18 divisors (see below), whose sum is σ = 10396582092. Its totient is φ = 4090456656.

The previous prime is 6646993571. The next prime is 6646993589. The reversal of 6646993587 is 7853996466.

6646993587 is a `hidden beast` number, since 6 + 6 + 46 + 9 + 9 + 3 + 587 = 666.

It is not a de Polignac number, because 6646993587 - 2⁴ = 6646993571 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6646993589) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2183553 + ... + 2186594.

It is an arithmetic number, because the mean of its divisors is an integer number (577587894).

Almost surely, 2^6646993587 is an apocalyptic number.

6646993587 is a deficient number, since it is larger than the sum of its proper divisors (3749588505).

6646993587 is a wasteful number, since it uses less digits than its factorization.

6646993587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4370179 (or 4370163 counting only the distinct ones).

The product of its digits is 58786560, while the sum is 63.

The square root of 6646993587 is about 81529.0965668086. The cubic root of 6646993587 is about 1880.2189260480.

The spelling of 6646993587 in words is "six billion, six hundred forty-six million, nine hundred ninety-three thousand, five hundred eighty-seven".