6516561687 has 8 divisors (see below), whose sum is σ = 9066520704. Its totient is φ = 4155488568.

The previous prime is 6516561683. The next prime is 6516561707. The reversal of 6516561687 is 7861656156.

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

It is not a de Polignac number, because 6516561687 - 2² = 6516561683 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6516561683) 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, 47221393 + ... + 47221530.

It is an arithmetic number, because the mean of its divisors is an integer number (1133315088).

Almost surely, 2^6516561687 is an apocalyptic number.

6516561687 is a deficient number, since it is larger than the sum of its proper divisors (2549959017).

6516561687 is a wasteful number, since it uses less digits than its factorization.

6516561687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94442949.

The product of its digits is 1814400, while the sum is 51.

The square root of 6516561687 is about 80725.2233629613. The cubic root of 6516561687 is about 1867.8392772219.

The spelling of 6516561687 in words is "six billion, five hundred sixteen million, five hundred sixty-one thousand, six hundred eighty-seven".