81845184 has 112 divisors (see below), whose sum is σ = 228636576. Its totient is φ = 25804800.

The previous prime is 81845167. The next prime is 81845209. The reversal of 81845184 is 48154818.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 291124 + ... + 291404.

It is an arithmetic number, because the mean of its divisors is an integer number (2041398).

Almost surely, 2^81845184 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81845184, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114318288).

81845184 is an abundant number, since it is smaller than the sum of its proper divisors (146791392).

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

81845184 is a wasteful number, since it uses less digits than its factorization.

81845184 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374 (or 364 counting only the distinct ones).

The product of its digits is 40960, while the sum is 39.

The square root of 81845184 is about 9046.8328159638. The cubic root of 81845184 is about 434.1745636269.

The spelling of 81845184 in words is "eighty-one million, eight hundred forty-five thousand, one hundred eighty-four".