104008991 has 4 divisors (see below), whose sum is σ = 105561432. Its totient is φ = 102456552.

The previous prime is 104008969. The next prime is 104008997. The reversal of 104008991 is 199800401.

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-104008991 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 (104008997) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 776120 + ... + 776253.

It is an arithmetic number, because the mean of its divisors is an integer number (26390358).

Almost surely, 2^104008991 is an apocalyptic number.

104008991 is a deficient number, since it is larger than the sum of its proper divisors (1552441).

104008991 is an equidigital number, since it uses as much as digits as its factorization.

104008991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1552440.

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 104008991 is about 10198.4798377013. The cubic root of 104008991 is about 470.2804889807.

It can be divided in two parts, 10400 and 8991, that added together give a palindrome (19391).

The spelling of 104008991 in words is "one hundred four million, eight thousand, nine hundred ninety-one".