40865809 has 8 divisors (see below), whose sum is σ = 42071400. Its totient is φ = 39676416.

The previous prime is 40865801. The next prime is 40865813. The reversal of 40865809 is 90856804.

It can be written as a sum of positive squares in 4 ways, for example, as 8410000 + 32455809 = 2900^2 + 5697^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 40865809 - 2³ = 40865801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40865801) 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, 1167 + ... + 9115.

It is an arithmetic number, because the mean of its divisors is an integer number (5258925).

Almost surely, 2^40865809 is an apocalyptic number.

It is an amenable number.

40865809 is a deficient number, since it is larger than the sum of its proper divisors (1205591).

40865809 is an equidigital number, since it uses as much as digits as its factorization.

40865809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8099.

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 40865809 is about 6392.6370927810. The cubic root of 40865809 is about 344.4451179738.

The spelling of 40865809 in words is "forty million, eight hundred sixty-five thousand, eight hundred nine".