19891103 has 2 divisors, whose sum is σ = 19891104. Its totient is φ = 19891102.

The previous prime is 19891099. The next prime is 19891117. The reversal of 19891103 is 30119891.

It is a weak prime.

It is an emirp because it is prime and its reverse (30119891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19891103 - 2² = 19891099 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19891103.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19891133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9945551 + 9945552.

It is an arithmetic number, because the mean of its divisors is an integer number (9945552).

Almost surely, 2^19891103 is an apocalyptic number.

19891103 is a deficient number, since it is larger than the sum of its proper divisors (1).

19891103 is an equidigital number, since it uses as much as digits as its factorization.

19891103 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 32.

The square root of 19891103 is about 4459.9442821632. The cubic root of 19891103 is about 270.9482115786.

The spelling of 19891103 in words is "nineteen million, eight hundred ninety-one thousand, one hundred three".