173316421 has 2 divisors, whose sum is σ = 173316422. Its totient is φ = 173316420.

The previous prime is 173316391. The next prime is 173316427. The reversal of 173316421 is 124613371.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 101304225 + 72012196 = 10065^2 + 8486^2 .

It is a cyclic number.

It is not a de Polignac number, because 173316421 - 2¹¹ = 173314373 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 173316421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (173316427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86658210 + 86658211.

It is an arithmetic number, because the mean of its divisors is an integer number (86658211).

Almost surely, 2^173316421 is an apocalyptic number.

It is an amenable number.

173316421 is a deficient number, since it is larger than the sum of its proper divisors (1).

173316421 is an equidigital number, since it uses as much as digits as its factorization.

173316421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3024, while the sum is 28.

The square root of 173316421 is about 13164.9694644538. The cubic root of 173316421 is about 557.5449725429.

Adding to 173316421 its reverse (124613371), we get a palindrome (297929792).

The spelling of 173316421 in words is "one hundred seventy-three million, three hundred sixteen thousand, four hundred twenty-one".