4905809 has 4 divisors (see below), whose sum is σ = 5194404. Its totient is φ = 4617216.

The previous prime is 4905799. The next prime is 4905829. The reversal of 4905809 is 9085094.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9085094 = 2 ⋅4542547.

It can be written as a sum of positive squares in 2 ways, for example, as 2739025 + 2166784 = 1655^2 + 1472^2 .

It is a cyclic number.

It is not a de Polignac number, because 4905809 - 2²⁰ = 3857233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4905829) 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, 144272 + ... + 144305.

It is an arithmetic number, because the mean of its divisors is an integer number (1298601).

Almost surely, 2^4905809 is an apocalyptic number.

It is an amenable number.

4905809 is a deficient number, since it is larger than the sum of its proper divisors (288595).

4905809 is a wasteful number, since it uses less digits than its factorization.

4905809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288594.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 4905809 is about 2214.9060928175. The cubic root of 4905809 is about 169.9170183245.

The spelling of 4905809 in words is "four million, nine hundred five thousand, eight hundred nine".