11858181871 has 4 divisors (see below), whose sum is σ = 11859071392. Its totient is φ = 11857292352.

The previous prime is 11858181869. The next prime is 11858181961. The reversal of 11858181871 is 17818185811.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17818185811 = 863 ⋅20646797.

It is a cyclic number.

It is not a de Polignac number, because 11858181871 - 2¹ = 11858181869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11858181271) 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, 424455 + ... + 451528.

It is an arithmetic number, because the mean of its divisors is an integer number (2964767848).

Almost surely, 2^11858181871 is an apocalyptic number.

11858181871 is a deficient number, since it is larger than the sum of its proper divisors (889521).

11858181871 is an equidigital number, since it uses as much as digits as its factorization.

11858181871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 889520.

The product of its digits is 143360, while the sum is 49.

The spelling of 11858181871 in words is "eleven billion, eight hundred fifty-eight million, one hundred eighty-one thousand, eight hundred seventy-one".