173221121 has 2 divisors, whose sum is σ = 173221122. Its totient is φ = 173221120.

The previous prime is 173221117. The next prime is 173221127. The reversal of 173221121 is 121122371.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 123321025 + 49900096 = 11105^2 + 7064^2 .

It is a cyclic number.

It is not a de Polignac number, because 173221121 - 2² = 173221117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 173221093 and 173221102.

It is not a weakly prime, because it can be changed into another prime (173221127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86610560 + 86610561.

It is an arithmetic number, because the mean of its divisors is an integer number (86610561).

Almost surely, 2^173221121 is an apocalyptic number.

It is an amenable number.

173221121 is a deficient number, since it is larger than the sum of its proper divisors (1).

173221121 is an equidigital number, since it uses as much as digits as its factorization.

173221121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 168, while the sum is 20.

The square root of 173221121 is about 13161.3495128729. The cubic root of 173221121 is about 557.4427629978.

Adding to 173221121 its reverse (121122371), we get a palindrome (294343492).

The spelling of 173221121 in words is "one hundred seventy-three million, two hundred twenty-one thousand, one hundred twenty-one".