40408091 has 4 divisors (see below), whose sum is σ = 40463952. Its totient is φ = 40352232.

The previous prime is 40408087. The next prime is 40408139. The reversal of 40408091 is 19080404.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 40408091 - 2² = 40408087 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 40408091.

It is not an unprimeable number, because it can be changed into a prime (40408021) 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 in 3 ways as a sum of consecutive naturals, for example, 26831 + ... + 28296.

It is an arithmetic number, because the mean of its divisors is an integer number (10115988).

Almost surely, 2^40408091 is an apocalyptic number.

40408091 is a deficient number, since it is larger than the sum of its proper divisors (55861).

40408091 is an equidigital number, since it uses as much as digits as its factorization.

40408091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55860.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 40408091 is about 6356.7358762182. The cubic root of 40408091 is about 343.1542993639.

Adding to 40408091 its reverse (19080404), we get a palindrome (59488495).

The spelling of 40408091 in words is "forty million, four hundred eight thousand, ninety-one".