6487809681 has 4 divisors (see below), whose sum is σ = 8650412912. Its totient is φ = 4325206452.

The previous prime is 6487809649. The next prime is 6487809721. The reversal of 6487809681 is 1869087846.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 6487809681 - 2⁵ = 6487809649 is a prime.

It is a super-2 number, since 2×6487809681² = 84183348913754643522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6487809631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1081301611 + ... + 1081301616.

It is an arithmetic number, because the mean of its divisors is an integer number (2162603228).

Almost surely, 2^6487809681 is an apocalyptic number.

It is an amenable number.

6487809681 is a deficient number, since it is larger than the sum of its proper divisors (2162603231).

6487809681 is a wasteful number, since it uses less digits than its factorization.

6487809681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2162603230.

The product of its (nonzero) digits is 4644864, while the sum is 57.

The square root of 6487809681 is about 80546.9408543863. The cubic root of 6487809681 is about 1865.0881687743.

The spelling of 6487809681 in words is "six billion, four hundred eighty-seven million, eight hundred nine thousand, six hundred eighty-one".