84972171827 has 4 divisors (see below), whose sum is σ = 84972856440. Its totient is φ = 84971487216.

The previous prime is 84972171821. The next prime is 84972171937. The reversal of 84972171827 is 72817127948.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 84972171827 - 2¹⁸ = 84971909683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84972171821) 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 3 ways as a sum of consecutive naturals, for example, 98018 + ... + 423735.

It is an arithmetic number, because the mean of its divisors is an integer number (21243214110).

Almost surely, 2^84972171827 is an apocalyptic number.

84972171827 is a deficient number, since it is larger than the sum of its proper divisors (684613).

84972171827 is a wasteful number, since it uses less digits than its factorization.

84972171827 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 684612.

The product of its digits is 3161088, while the sum is 56.

The spelling of 84972171827 in words is "eighty-four billion, nine hundred seventy-two million, one hundred seventy-one thousand, eight hundred twenty-seven".