180775981 has 4 divisors (see below), whose sum is σ = 181322464. Its totient is φ = 180229500.

The previous prime is 180775979. The next prime is 180775993. The reversal of 180775981 is 189577081.

180775981 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 a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 180775981 - 2¹ = 180775979 is a prime.

It is a super-2 number, since 2×180775981² = 65359910613024722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (180775901) 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, 272745 + ... + 273406.

It is an arithmetic number, because the mean of its divisors is an integer number (45330616).

Almost surely, 2^180775981 is an apocalyptic number.

It is an amenable number.

180775981 is a deficient number, since it is larger than the sum of its proper divisors (546483).

180775981 is an equidigital number, since it uses as much as digits as its factorization.

180775981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546482.

The product of its (nonzero) digits is 141120, while the sum is 46.

The square root of 180775981 is about 13445.2958688160. The cubic root of 180775981 is about 565.4318164936.

It can be divided in two parts, 180 and 775981, that added together give a square (776161 = 881²).

The spelling of 180775981 in words is "one hundred eighty million, seven hundred seventy-five thousand, nine hundred eighty-one".