100440991 has 8 divisors (see below), whose sum is σ = 117459584. Its totient is φ = 84089880.

The previous prime is 100440943. The next prime is 100441009. The reversal of 100440991 is 199044001.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 100440991 - 2¹⁵ = 100408223 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 (100440911) 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 in 7 ways as a sum of consecutive naturals, for example, 166545 + ... + 167146.

It is an arithmetic number, because the mean of its divisors is an integer number (14682448).

Almost surely, 2^100440991 is an apocalyptic number.

100440991 is a deficient number, since it is larger than the sum of its proper divisors (17018593).

100440991 is an equidigital number, since it uses as much as digits as its factorization.

100440991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333741.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 100440991 is about 10022.0252943205. The cubic root of 100440991 is about 464.8401824851.

Adding to 100440991 its reverse (199044001), we get a palindrome (299484992).

The spelling of 100440991 in words is "one hundred million, four hundred forty thousand, nine hundred ninety-one".