91819109103 has 4 divisors (see below), whose sum is σ = 122425478808. Its totient is φ = 61212739400.

The previous prime is 91819109089. The next prime is 91819109131. The reversal of 91819109103 is 30190191819.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30190191819 = 3 ⋅10063397273.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91819109103 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91819109303) 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, 15303184848 + ... + 15303184853.

It is an arithmetic number, because the mean of its divisors is an integer number (30606369702).

Almost surely, 2^91819109103 is an apocalyptic number.

91819109103 is a deficient number, since it is larger than the sum of its proper divisors (30606369705).

91819109103 is a wasteful number, since it uses less digits than its factorization.

91819109103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30606369704.

The product of its (nonzero) digits is 17496, while the sum is 42.

The spelling of 91819109103 in words is "ninety-one billion, eight hundred nineteen million, one hundred nine thousand, one hundred three".