104431991 has 2 divisors, whose sum is σ = 104431992. Its totient is φ = 104431990.

The previous prime is 104431933. The next prime is 104432017. The reversal of 104431991 is 199134401.

It is a strong prime.

It is an emirp because it is prime and its reverse (199134401) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 104431991 - 2¹⁰ = 104430967 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (104931991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52215995 + 52215996.

It is an arithmetic number, because the mean of its divisors is an integer number (52215996).

Almost surely, 2^104431991 is an apocalyptic number.

104431991 is a deficient number, since it is larger than the sum of its proper divisors (1).

104431991 is an equidigital number, since it uses as much as digits as its factorization.

104431991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 104431991 is about 10219.1971798180. The cubic root of 104431991 is about 470.9171633508.

The spelling of 104431991 in words is "one hundred four million, four hundred thirty-one thousand, nine hundred ninety-one".