166241321 has 2 divisors, whose sum is σ = 166241322. Its totient is φ = 166241320.

The previous prime is 166241297. The next prime is 166241323. The reversal of 166241321 is 123142661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 165894400 + 346921 = 12880^2 + 589^2 .

It is an emirp because it is prime and its reverse (123142661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166241321 - 2¹⁴ = 166224937 is a prime.

Together with 166241323, 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 (166241323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83120660 + 83120661.

It is an arithmetic number, because the mean of its divisors is an integer number (83120661).

Almost surely, 2^166241321 is an apocalyptic number.

It is an amenable number.

166241321 is a deficient number, since it is larger than the sum of its proper divisors (1).

166241321 is an equidigital number, since it uses as much as digits as its factorization.

166241321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 26.

The square root of 166241321 is about 12893.4603966507. The cubic root of 166241321 is about 549.8526558471.

Adding to 166241321 its reverse (123142661), we get a palindrome (289383982).

The spelling of 166241321 in words is "one hundred sixty-six million, two hundred forty-one thousand, three hundred twenty-one".