180221 has 2 divisors, whose sum is σ = 180222. Its totient is φ = 180220.

The previous prime is 180211. The next prime is 180233. The reversal of 180221 is 122081.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 151321 + 28900 = 389^2 + 170^2 .

It is an emirp because it is prime and its reverse (122081) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-180221 is a prime.

It is a Chen prime.

It is a plaindrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 180196 and 180205.

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 180221.

It is not a weakly prime, because it can be changed into another prime (180211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90110 + 90111.

It is an arithmetic number, because the mean of its divisors is an integer number (90111).

2¹⁸⁰²²¹ is an apocalyptic number.

It is an amenable number.

180221 is a deficient number, since it is larger than the sum of its proper divisors (1).

180221 is an equidigital number, since it uses as much as digits as its factorization.

180221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 180221 is about 424.5244398147. The cubic root of 180221 is about 56.4852599448.

The spelling of 180221 in words is "one hundred eighty thousand, two hundred twenty-one".