181020445 has 4 divisors (see below), whose sum is σ = 217224540. Its totient is φ = 144816352.

The previous prime is 181020443. The next prime is 181020451. The reversal of 181020445 is 544020181.

181020445 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 544020181 = 3691 ⋅147391.

It can be written as a sum of positive squares in 2 ways, for example, as 91642329 + 89378116 = 9573^2 + 9454^2 .

It is a cyclic number.

It is not a de Polignac number, because 181020445 - 2¹ = 181020443 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (181020443) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18102040 + ... + 18102049.

It is an arithmetic number, because the mean of its divisors is an integer number (54306135).

Almost surely, 2^181020445 is an apocalyptic number.

It is an amenable number.

181020445 is a deficient number, since it is larger than the sum of its proper divisors (36204095).

181020445 is an equidigital number, since it uses as much as digits as its factorization.

181020445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36204094.

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 181020445 is about 13454.3838580591. The cubic root of 181020445 is about 565.6865801721.

The spelling of 181020445 in words is "one hundred eighty-one million, twenty thousand, four hundred forty-five".