85644381834 has 128 divisors (see below), whose sum is σ = 215351136000. Its totient is φ = 24991545600.

The previous prime is 85644381833. The next prime is 85644381937. The reversal of 85644381834 is 43818344658.

It is a happy number.

85644381834 is a `hidden beast` number, since 8 + 564 + 4 + 38 + 18 + 34 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (85644381833) 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 63 ways as a sum of consecutive naturals, for example, 6694524 + ... + 6707304.

It is an arithmetic number, because the mean of its divisors is an integer number (1682430750).

Almost surely, 2^85644381834 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 85644381834, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107675568000).

85644381834 is an abundant number, since it is smaller than the sum of its proper divisors (129706754166).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

85644381834 is a wasteful number, since it uses less digits than its factorization.

85644381834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13221 (or 13215 counting only the distinct ones).

The product of its digits is 8847360, while the sum is 54.

The spelling of 85644381834 in words is "eighty-five billion, six hundred forty-four million, three hundred eighty-one thousand, eight hundred thirty-four".