6506781 has 8 divisors (see below), whose sum is σ = 8698560. Its totient is φ = 4326432.

The previous prime is 6506779. The next prime is 6506789. The reversal of 6506781 is 1876056.

6506781 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 6506781 - 2¹ = 6506779 is a prime.

It is a super-2 number, since 2×6506781² = 84676397963922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6506789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1425 + ... + 3878.

It is an arithmetic number, because the mean of its divisors is an integer number (1087320).

Almost surely, 2^6506781 is an apocalyptic number.

It is an amenable number.

6506781 is a deficient number, since it is larger than the sum of its proper divisors (2191779).

6506781 is a wasteful number, since it uses less digits than its factorization.

6506781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5715.

The product of its (nonzero) digits is 10080, while the sum is 33.

The square root of 6506781 is about 2550.8392736509. The cubic root of 6506781 is about 186.6904331275.

The spelling of 6506781 in words is "six million, five hundred six thousand, seven hundred eighty-one".