40312009 has 2 divisors, whose sum is σ = 40312010. Its totient is φ = 40312008.

The previous prime is 40312007. The next prime is 40312039. The reversal of 40312009 is 90021304.

40312009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33315984 + 6996025 = 5772^2 + 2645^2 .

It is a cyclic number.

It is not a de Polignac number, because 40312009 - 2¹ = 40312007 is a prime.

Together with 40312007, it forms a pair of twin primes.

It is equal to p_2451520 and since 40312009 and 2451520 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (40312003) 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 as a sum of consecutive naturals, namely, 20156004 + 20156005.

It is an arithmetic number, because the mean of its divisors is an integer number (20156005).

Almost surely, 2^40312009 is an apocalyptic number.

It is an amenable number.

40312009 is a deficient number, since it is larger than the sum of its proper divisors (1).

40312009 is an equidigital number, since it uses as much as digits as its factorization.

40312009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 40312009 is about 6349.1738832702. The cubic root of 40312009 is about 342.8821004236.

The spelling of 40312009 in words is "forty million, three hundred twelve thousand, nine".