40399309 has 8 divisors (see below), whose sum is σ = 41477688. Its totient is φ = 39325440.

The previous prime is 40399297. The next prime is 40399313. The reversal of 40399309 is 90399304.

40399309 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 4937284 + 35462025 = 2222^2 + 5955^2 .

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 40399309 - 2⁵ = 40399277 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 (40399319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24499 + ... + 26095.

It is an arithmetic number, because the mean of its divisors is an integer number (5184711).

Almost surely, 2^40399309 is an apocalyptic number.

It is an amenable number.

40399309 is a deficient number, since it is larger than the sum of its proper divisors (1078379).

40399309 is a wasteful number, since it uses less digits than its factorization.

40399309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2255.

The product of its (nonzero) digits is 26244, while the sum is 37.

The square root of 40399309 is about 6356.0450753594. The cubic root of 40399309 is about 343.1294380113.

The spelling of 40399309 in words is "forty million, three hundred ninety-nine thousand, three hundred nine".