6728905 has 4 divisors (see below), whose sum is σ = 8074692. Its totient is φ = 5383120.

The previous prime is 6728881. The next prime is 6728947. The reversal of 6728905 is 5098276.

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 5143824 + 1585081 = 2268^2 + 1259^2 .

It is not a de Polignac number, because 6728905 - 2⁵ = 6728873 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 672886 + ... + 672895.

It is an arithmetic number, because the mean of its divisors is an integer number (2018673).

Almost surely, 2^6728905 is an apocalyptic number.

It is an amenable number.

6728905 is a deficient number, since it is larger than the sum of its proper divisors (1345787).

6728905 is a wasteful number, since it uses less digits than its factorization.

6728905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1345786.

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 6728905 is about 2594.0132998888. The cubic root of 6728905 is about 188.7910777078.

The spelling of 6728905 in words is "six million, seven hundred twenty-eight thousand, nine hundred five".