20191910200091 has 4 divisors (see below), whose sum is σ = 23076468800112. Its totient is φ = 17307351600072.

The previous prime is 20191910200087. The next prime is 20191910200169. The reversal of 20191910200091 is 19000201919102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20191910200091 - 2² = 20191910200087 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20191910200001) 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, 1442279300000 + ... + 1442279300013.

It is an arithmetic number, because the mean of its divisors is an integer number (5769117200028).

Almost surely, 2^{20191910200091} is an apocalyptic number.

20191910200091 is a deficient number, since it is larger than the sum of its proper divisors (2884558600021).

20191910200091 is an equidigital number, since it uses as much as digits as its factorization.

20191910200091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2884558600020.

The product of its (nonzero) digits is 2916, while the sum is 35.

The spelling of 20191910200091 in words is "twenty trillion, one hundred ninety-one billion, nine hundred ten million, two hundred thousand, ninety-one".