40615391 has 2 divisors, whose sum is σ = 40615392. Its totient is φ = 40615390.

The previous prime is 40615387. The next prime is 40615403. The reversal of 40615391 is 19351604.

40615391 is nontrivially palindromic in base 14.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 40615391 - 2² = 40615387 is a prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40615361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20307695 + 20307696.

It is an arithmetic number, because the mean of its divisors is an integer number (20307696).

Almost surely, 2^40615391 is an apocalyptic number.

40615391 is a deficient number, since it is larger than the sum of its proper divisors (1).

40615391 is an equidigital number, since it uses as much as digits as its factorization.

40615391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 40615391 is about 6373.0205554352. The cubic root of 40615391 is about 343.7401109662.

Adding to 40615391 its reverse (19351604), we get a palindrome (59966995).

The spelling of 40615391 in words is "forty million, six hundred fifteen thousand, three hundred ninety-one".