40040393 has 2 divisors, whose sum is σ = 40040394. Its totient is φ = 40040392.

The previous prime is 40040293. The next prime is 40040411. The reversal of 40040393 is 39304004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39778249 + 262144 = 6307^2 + 512^2 .

It is a cyclic number.

It is not a de Polignac number, because 40040393 - 2¹⁴ = 40024009 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (40040093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20020196 + 20020197.

It is an arithmetic number, because the mean of its divisors is an integer number (20020197).

Almost surely, 2^40040393 is an apocalyptic number.

It is an amenable number.

40040393 is a deficient number, since it is larger than the sum of its proper divisors (1).

40040393 is an equidigital number, since it uses as much as digits as its factorization.

40040393 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 23.

The square root of 40040393 is about 6327.7478616013. The cubic root of 40040393 is about 342.1102690379.

Adding to 40040393 its reverse (39304004), we get a palindrome (79344397).

The spelling of 40040393 in words is "forty million, forty thousand, three hundred ninety-three".