84171517859 has 24 divisors (see below), whose sum is σ = 100836550416. Its totient is φ = 69782328000.

The previous prime is 84171517849. The next prime is 84171517907. The reversal of 84171517859 is 95871517148.

It is a happy number.

It is not a de Polignac number, because 84171517859 - 2⁸ = 84171517603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84171517849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 191792 + ... + 452909.

It is an arithmetic number, because the mean of its divisors is an integer number (4201522934).

Almost surely, 2^84171517859 is an apocalyptic number.

84171517859 is a deficient number, since it is larger than the sum of its proper divisors (16665032557).

84171517859 is a wasteful number, since it uses less digits than its factorization.

84171517859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 644819 (or 644808 counting only the distinct ones).

The product of its digits is 2822400, while the sum is 56.

The spelling of 84171517859 in words is "eighty-four billion, one hundred seventy-one million, five hundred seventeen thousand, eight hundred fifty-nine".