191118653881 has 4 divisors (see below), whose sum is σ = 191119923792. Its totient is φ = 191117383972.

The previous prime is 191118653879. The next prime is 191118653963. The reversal of 191118653881 is 188356811191.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 188356811191 = 17 ⋅11079812423.

It is a cyclic number.

It is not a de Polignac number, because 191118653881 - 2¹ = 191118653879 is a prime.

It is a super-2 number, since 2×191118653881² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (191118653081) 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, 373255 + ... + 722188.

It is an arithmetic number, because the mean of its divisors is an integer number (47779980948).

Almost surely, 2^191118653881 is an apocalyptic number.

It is an amenable number.

191118653881 is a deficient number, since it is larger than the sum of its proper divisors (1269911).

191118653881 is a wasteful number, since it uses less digits than its factorization.

191118653881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1269910.

The product of its digits is 414720, while the sum is 52.

The spelling of 191118653881 in words is "one hundred ninety-one billion, one hundred eighteen million, six hundred fifty-three thousand, eight hundred eighty-one".