40517809 has 2 divisors, whose sum is σ = 40517810. Its totient is φ = 40517808.

The previous prime is 40517779. The next prime is 40517819. The reversal of 40517809 is 90871504.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31080625 + 9437184 = 5575^2 + 3072^2 .

It is a cyclic number.

It is not a de Polignac number, because 40517809 - 2⁵ = 40517777 is a prime.

It is not a weakly prime, because it can be changed into another prime (40517819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20258904 + 20258905.

It is an arithmetic number, because the mean of its divisors is an integer number (20258905).

Almost surely, 2^40517809 is an apocalyptic number.

It is an amenable number.

40517809 is a deficient number, since it is larger than the sum of its proper divisors (1).

40517809 is an equidigital number, since it uses as much as digits as its factorization.

40517809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 40517809 is about 6365.3600840801. The cubic root of 40517809 is about 343.4646017254.

The spelling of 40517809 in words is "forty million, five hundred seventeen thousand, eight hundred nine".