18711192971 has 4 divisors (see below), whose sum is σ = 18715607112. Its totient is φ = 18706778832.

The previous prime is 18711192943. The next prime is 18711192977. The reversal of 18711192971 is 17929111781.

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-18711192971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18711192977) 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, 2200706 + ... + 2209191.

It is an arithmetic number, because the mean of its divisors is an integer number (4678901778).

Almost surely, 2^18711192971 is an apocalyptic number.

18711192971 is a deficient number, since it is larger than the sum of its proper divisors (4414141).

18711192971 is an equidigital number, since it uses as much as digits as its factorization.

18711192971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4414140.

The product of its digits is 63504, while the sum is 47.

It can be divided in two parts, 187111 and 92971, that added together give a palindrome (280082).

The spelling of 18711192971 in words is "eighteen billion, seven hundred eleven million, one hundred ninety-two thousand, nine hundred seventy-one".