40003391 has 2 divisors, whose sum is σ = 40003392. Its totient is φ = 40003390.

The previous prime is 40003387. The next prime is 40003409. The reversal of 40003391 is 19330004.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 40003391 - 2² = 40003387 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40003991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20001695 + 20001696.

It is an arithmetic number, because the mean of its divisors is an integer number (20001696).

Almost surely, 2^40003391 is an apocalyptic number.

40003391 is a deficient number, since it is larger than the sum of its proper divisors (1).

40003391 is an equidigital number, since it uses as much as digits as its factorization.

40003391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 40003391 is about 6324.8233967440. The cubic root of 40003391 is about 342.0048532763.

Adding to 40003391 its reverse (19330004), we get a palindrome (59333395).

The spelling of 40003391 in words is "forty million, three thousand, three hundred ninety-one".