40540405391 has 2 divisors, whose sum is σ = 40540405392. Its totient is φ = 40540405390.

The previous prime is 40540405379. The next prime is 40540405487. The reversal of 40540405391 is 19350404504.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40540405391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40543405391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20270202695 + 20270202696.

It is an arithmetic number, because the mean of its divisors is an integer number (20270202696).

Almost surely, 2^40540405391 is an apocalyptic number.

40540405391 is a deficient number, since it is larger than the sum of its proper divisors (1).

40540405391 is an equidigital number, since it uses as much as digits as its factorization.

40540405391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43200, while the sum is 35.

Adding to 40540405391 its reverse (19350404504), we get a palindrome (59890809895).

The spelling of 40540405391 in words is "forty billion, five hundred forty million, four hundred five thousand, three hundred ninety-one".