40438609 has 2 divisors, whose sum is σ = 40438610. Its totient is φ = 40438608.

The previous prime is 40438589. The next prime is 40438613. The reversal of 40438609 is 90683404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39753025 + 685584 = 6305^2 + 828^2 .

It is a cyclic number.

It is not a de Polignac number, because 40438609 - 2¹⁹ = 39914321 is a prime.

It is not a weakly prime, because it can be changed into another prime (40438639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20219304 + 20219305.

It is an arithmetic number, because the mean of its divisors is an integer number (20219305).

Almost surely, 2^40438609 is an apocalyptic number.

It is an amenable number.

40438609 is a deficient number, since it is larger than the sum of its proper divisors (1).

40438609 is an equidigital number, since it uses as much as digits as its factorization.

40438609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 40438609 is about 6359.1358689684. The cubic root of 40438609 is about 343.2406661232.

The spelling of 40438609 in words is "forty million, four hundred thirty-eight thousand, six hundred nine".