181800720 has 160 divisors (see below), whose sum is σ = 663171840. Its totient is φ = 45619200.

The previous prime is 181800719. The next prime is 181800761. The reversal of 181800720 is 27008181.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34245 + ... + 39195.

It is an arithmetic number, because the mean of its divisors is an integer number (4144824).

Almost surely, 2^181800720 is an apocalyptic number.

181800720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 181800720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (331585920).

181800720 is an abundant number, since it is smaller than the sum of its proper divisors (481371120).

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

181800720 is a wasteful number, since it uses less digits than its factorization.

181800720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4990 (or 4978 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 27.

The square root of 181800720 is about 13483.3497321697. The cubic root of 181800720 is about 566.4981982858.

The spelling of 181800720 in words is "one hundred eighty-one million, eight hundred thousand, seven hundred twenty".