6511985 has 4 divisors (see below), whose sum is σ = 7814388. Its totient is φ = 5209584.

The previous prime is 6511961. The next prime is 6511997. The reversal of 6511985 is 5891156.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 790321 + 5721664 = 889^2 + 2392^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6511985 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 651194 + ... + 651203.

It is an arithmetic number, because the mean of its divisors is an integer number (1953597).

Almost surely, 2^6511985 is an apocalyptic number.

It is an amenable number.

6511985 is a deficient number, since it is larger than the sum of its proper divisors (1302403).

6511985 is a wasteful number, since it uses less digits than its factorization.

6511985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1302402.

The product of its digits is 10800, while the sum is 35.

The square root of 6511985 is about 2551.8591262058. The cubic root of 6511985 is about 186.7401903538.

The spelling of 6511985 in words is "six million, five hundred eleven thousand, nine hundred eighty-five".