181005500 has 48 divisors (see below), whose sum is σ = 425740224. Its totient is φ = 66830400.

The previous prime is 181005491. The next prime is 181005521. The reversal of 181005500 is 5500181.

It is a Harshad number since it is a multiple of its sum of digits (20).

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, 7424 + ... + 20423.

It is an arithmetic number, because the mean of its divisors is an integer number (8869588).

Almost surely, 2^181005500 is an apocalyptic number.

181005500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

181005500 is an abundant number, since it is smaller than the sum of its proper divisors (244734724).

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

181005500 is a wasteful number, since it uses less digits than its factorization.

181005500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27879 (or 27867 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 20.

The square root of 181005500 is about 13453.8284514111. The cubic root of 181005500 is about 565.6710120989.

Adding to 181005500 its reverse (5500181), we get a palindrome (186505681).

The spelling of 181005500 in words is "one hundred eighty-one million, five thousand, five hundred".