40129909 has 2 divisors, whose sum is σ = 40129910. Its totient is φ = 40129908.

The previous prime is 40129907. The next prime is 40129913. The reversal of 40129909 is 90992104.

40129909 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., 40068900 + 61009 = 6330^2 + 247^2 .

It is a cyclic number.

It is not a de Polignac number, because 40129909 - 2¹ = 40129907 is a prime.

It is a super-2 number, since 2×40129909² = 3220819192696562, which contains 22 as substring.

Together with 40129907, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40129907) 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, 20064954 + 20064955.

It is an arithmetic number, because the mean of its divisors is an integer number (20064955).

Almost surely, 2^40129909 is an apocalyptic number.

It is an amenable number.

40129909 is a deficient number, since it is larger than the sum of its proper divisors (1).

40129909 is an equidigital number, since it uses as much as digits as its factorization.

40129909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 34.

The square root of 40129909 is about 6334.8172033611. The cubic root of 40129909 is about 342.3650246914.

The spelling of 40129909 in words is "forty million, one hundred twenty-nine thousand, nine hundred nine".