40400040409 has 2 divisors, whose sum is σ = 40400040410. Its totient is φ = 40400040408.

The previous prime is 40400040407. The next prime is 40400040413. The reversal of 40400040409 is 90404000404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35366563600 + 5033476809 = 188060^2 + 70947^2 .

It is a cyclic number.

It is not a de Polignac number, because 40400040409 - 2¹ = 40400040407 is a prime.

Together with 40400040407, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (40400040407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20200020204 + 20200020205.

It is an arithmetic number, because the mean of its divisors is an integer number (20200020205).

Almost surely, 2^40400040409 is an apocalyptic number.

It is an amenable number.

40400040409 is a deficient number, since it is larger than the sum of its proper divisors (1).

40400040409 is an equidigital number, since it uses as much as digits as its factorization.

40400040409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 25.

The spelling of 40400040409 in words is "forty billion, four hundred million, forty thousand, four hundred nine".