181332864 has 128 divisors (see below), whose sum is σ = 543456000. Its totient is φ = 59512320.

The previous prime is 181332847. The next prime is 181332869. The reversal of 181332864 is 468233181.

181332864 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181332869) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 245007 + ... + 245745.

It is an arithmetic number, because the mean of its divisors is an integer number (4245750).

Almost surely, 2^181332864 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 181332864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (271728000).

181332864 is an abundant number, since it is smaller than the sum of its proper divisors (362123136).

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

181332864 is an equidigital number, since it uses as much as digits as its factorization.

181332864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 833 (or 815 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 181332864 is about 13465.9891578747. The cubic root of 181332864 is about 566.0118282603.

The spelling of 181332864 in words is "one hundred eighty-one million, three hundred thirty-two thousand, eight hundred sixty-four".