72221 has 2 divisors, whose sum is σ = 72222. Its totient is φ = 72220.

The previous prime is 72211. The next prime is 72223. The reversal of 72221 is 12227.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52900 + 19321 = 230^2 + 139^2 .

It is an emirp because it is prime and its reverse (12227) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72221 - 2¹⁴ = 55837 is a prime.

Together with 72223, it forms a pair of twin primes.

It is a Chen prime.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 72196 and 72205.

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 72221.

It is not a weakly prime, because it can be changed into another prime (72223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36110 + 36111.

It is an arithmetic number, because the mean of its divisors is an integer number (36111).

2⁷²²²¹ is an apocalyptic number.

It is an amenable number.

72221 is a deficient number, since it is larger than the sum of its proper divisors (1).

72221 is an equidigital number, since it uses as much as digits as its factorization.

72221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56, while the sum is 14.

The square root of 72221 is about 268.7396509635. The cubic root of 72221 is about 41.6441976634.

Adding to 72221 its reverse (12227), we get a palindrome (84448).

The spelling of 72221 in words is "seventy-two thousand, two hundred twenty-one", and thus it is an iban number.