4091509 has 4 divisors (see below), whose sum is σ = 4332204. Its totient is φ = 3850816.

The previous prime is 4091471. The next prime is 4091537. The reversal of 4091509 is 9051904.

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 3276100 + 815409 = 1810^2 + 903^2 .

It is a cyclic number.

It is not a de Polignac number, because 4091509 - 2⁹ = 4090997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4091569) 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, 120322 + ... + 120355.

It is an arithmetic number, because the mean of its divisors is an integer number (1083051).

Almost surely, 2^4091509 is an apocalyptic number.

It is an amenable number.

4091509 is a deficient number, since it is larger than the sum of its proper divisors (240695).

4091509 is a wasteful number, since it uses less digits than its factorization.

4091509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240694.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 4091509 is about 2022.7478834496. The cubic root of 4091509 is about 159.9415020525.

The spelling of 4091509 in words is "four million, ninety-one thousand, five hundred nine".