181442664 has 96 divisors (see below), whose sum is σ = 533169000. Its totient is φ = 55411200.

The previous prime is 181442627. The next prime is 181442669. The reversal of 181442664 is 466244181.

It is a happy number.

181442664 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 26440164 + 155002500 = 5142^2 + 12450^2 .

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 not an unprimeable number, because it can be changed into a prime (181442669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 138814 + ... + 140114.

Almost surely, 2^181442664 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 181442664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (266584500).

181442664 is an abundant number, since it is smaller than the sum of its proper divisors (351726336).

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

181442664 is a wasteful number, since it uses less digits than its factorization.

181442664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1475 (or 1468 counting only the distinct ones).

The product of its digits is 36864, while the sum is 36.

The square root of 181442664 is about 13470.0654786827. The cubic root of 181442664 is about 566.1260483336.

It can be divided in two parts, 181442 and 664, that added together give a triangular number (182106 = T₆₀₃).

The spelling of 181442664 in words is "one hundred eighty-one million, four hundred forty-two thousand, six hundred sixty-four".