40356809 has 4 divisors (see below), whose sum is σ = 40909716. Its totient is φ = 39803904.

The previous prime is 40356787. The next prime is 40356821. The reversal of 40356809 is 90865304.

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 34339600 + 6017209 = 5860^2 + 2453^2 .

It is a cyclic number.

It is not a de Polignac number, because 40356809 - 2⁸ = 40356553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40356859) 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, 276344 + ... + 276489.

It is an arithmetic number, because the mean of its divisors is an integer number (10227429).

Almost surely, 2^40356809 is an apocalyptic number.

It is an amenable number.

40356809 is a deficient number, since it is larger than the sum of its proper divisors (552907).

40356809 is an equidigital number, since it uses as much as digits as its factorization.

40356809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 552906.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 40356809 is about 6352.7009216553. The cubic root of 40356809 is about 343.0090719437.

The spelling of 40356809 in words is "forty million, three hundred fifty-six thousand, eight hundred nine".