8440991 has 4 divisors (see below), whose sum is σ = 9090312. Its totient is φ = 7791672.

The previous prime is 8440979. The next prime is 8441009. The reversal of 8440991 is 1990448.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8440991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8440961) 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, 324641 + ... + 324666.

It is an arithmetic number, because the mean of its divisors is an integer number (2272578).

Almost surely, 2^8440991 is an apocalyptic number.

8440991 is a deficient number, since it is larger than the sum of its proper divisors (649321).

8440991 is a wasteful number, since it uses less digits than its factorization.

8440991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649320.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 8440991 is about 2905.3383623943. The cubic root of 8440991 is about 203.6093945048.

The spelling of 8440991 in words is "eight million, four hundred forty thousand, nine hundred ninety-one".