180541721 has 2 divisors, whose sum is σ = 180541722. Its totient is φ = 180541720.

The previous prime is 180541687. The next prime is 180541723. The reversal of 180541721 is 127145081.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 180526096 + 15625 = 13436^2 + 125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-180541721 is a prime.

Together with 180541723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (180541723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90270860 + 90270861.

It is an arithmetic number, because the mean of its divisors is an integer number (90270861).

Almost surely, 2^180541721 is an apocalyptic number.

It is an amenable number.

180541721 is a deficient number, since it is larger than the sum of its proper divisors (1).

180541721 is an equidigital number, since it uses as much as digits as its factorization.

180541721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2240, while the sum is 29.

The square root of 180541721 is about 13436.5814476749. The cubic root of 180541721 is about 565.1874711378.

The spelling of 180541721 in words is "one hundred eighty million, five hundred forty-one thousand, seven hundred twenty-one".