87121839191 has 8 divisors (see below), whose sum is σ = 88981058304. Its totient is φ = 85262851960.

The previous prime is 87121839163. The next prime is 87121839199. The reversal of 87121839191 is 19193812178.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 87121839191 - 2²⁶ = 87054730327 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 (87121839199) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 852296 + ... + 949026.

It is an arithmetic number, because the mean of its divisors is an integer number (11122632288).

Almost surely, 2^87121839191 is an apocalyptic number.

87121839191 is a deficient number, since it is larger than the sum of its proper divisors (1859219113).

87121839191 is a wasteful number, since it uses less digits than its factorization.

87121839191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115941.

The product of its digits is 217728, while the sum is 50.

The spelling of 87121839191 in words is "eighty-seven billion, one hundred twenty-one million, eight hundred thirty-nine thousand, one hundred ninety-one".