6499885865 has 24 divisors (see below), whose sum is σ = 8592528840. Its totient is φ = 4716645120.

The previous prime is 6499885853. The next prime is 6499885871. The reversal of 6499885865 is 5685889946.

It can be written as a sum of positive squares in 4 ways, for example, as 3692263696 + 2807622169 = 60764^2 + 52987^2 .

It is not a de Polignac number, because 6499885865 - 2¹⁰ = 6499884841 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6499885795 and 6499885804.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 264731 + ... + 288239.

It is an arithmetic number, because the mean of its divisors is an integer number (358022035).

Almost surely, 2^6499885865 is an apocalyptic number.

It is an amenable number.

6499885865 is a deficient number, since it is larger than the sum of its proper divisors (2092642975).

6499885865 is a wasteful number, since it uses less digits than its factorization.

6499885865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23993 (or 23982 counting only the distinct ones).

The product of its digits is 149299200, while the sum is 68.

The square root of 6499885865 is about 80621.8696446566. The cubic root of 6499885865 is about 1866.2446550072.

The spelling of 6499885865 in words is "six billion, four hundred ninety-nine million, eight hundred eighty-five thousand, eight hundred sixty-five".