181820045 has 24 divisors (see below), whose sum is σ = 240743832. Its totient is φ = 131725440.

The previous prime is 181820033. The next prime is 181820069. The reversal of 181820045 is 540028181.

It can be written as a sum of positive squares in 4 ways, for example, as 37002889 + 144817156 = 6083^2 + 12034^2 .

It is a de Polignac number, because none of the positive numbers 2^k-181820045 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 239807 + ... + 240563.

It is an arithmetic number, because the mean of its divisors is an integer number (10030993).

Almost surely, 2^181820045 is an apocalyptic number.

It is an amenable number.

181820045 is a deficient number, since it is larger than the sum of its proper divisors (58923787).

181820045 is a wasteful number, since it uses less digits than its factorization.

181820045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1181 (or 1170 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 29.

The square root of 181820045 is about 13484.0663377188. The cubic root of 181820045 is about 566.5182700615.

The spelling of 181820045 in words is "one hundred eighty-one million, eight hundred twenty thousand, forty-five".