180981 has 8 divisors (see below), whose sum is σ = 268160. Its totient is φ = 120636.

The previous prime is 180959. The next prime is 181001. The reversal of 180981 is 189081.

It is not a de Polignac number, because 180981 - 2⁵ = 180949 is a prime.

It is a super-2 number, since 2×180981² = 65508244722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 6703 = 180981 / (1 + 8 + 0 + 9 + 8 + 1).

It is a Duffinian number.

180981 is a lucky number.

It is a plaindrome in base 12.

It is a zygodrome in base 12.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 180981.

It is not an unprimeable number, because it can be changed into a prime (180181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3325 + ... + 3378.

It is an arithmetic number, because the mean of its divisors is an integer number (33520).

2¹⁸⁰⁹⁸¹ is an apocalyptic number.

It is an amenable number.

180981 is a deficient number, since it is larger than the sum of its proper divisors (87179).

180981 is an equidigital number, since it uses as much as digits as its factorization.

180981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6712 (or 6706 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 180981 is about 425.4186173641. The cubic root of 180981 is about 56.5645488813.

Subtracting 180981 from its reverse (189081), we obtain a square (8100 = 90²).

The spelling of 180981 in words is "one hundred eighty thousand, nine hundred eighty-one".