40031491 has 2 divisors, whose sum is σ = 40031492. Its totient is φ = 40031490.

The previous prime is 40031489. The next prime is 40031501. The reversal of 40031491 is 19413004.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 40031491 - 2¹ = 40031489 is a prime.

Together with 40031489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (40031401) 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, 20015745 + 20015746.

It is an arithmetic number, because the mean of its divisors is an integer number (20015746).

Almost surely, 2^40031491 is an apocalyptic number.

40031491 is a deficient number, since it is larger than the sum of its proper divisors (1).

40031491 is an equidigital number, since it uses as much as digits as its factorization.

40031491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 40031491 is about 6327.0444126780. The cubic root of 40031491 is about 342.0849138811.

Adding to 40031491 its reverse (19413004), we get a palindrome (59444495).

The spelling of 40031491 in words is "forty million, thirty-one thousand, four hundred ninety-one".