173821213 has 2 divisors, whose sum is σ = 173821214. Its totient is φ = 173821212.

The previous prime is 173821163. The next prime is 173821223. The reversal of 173821213 is 312128371.

173821213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 148791204 + 25030009 = 12198^2 + 5003^2 .

It is a cyclic number.

It is not a de Polignac number, because 173821213 - 2⁹ = 173820701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (173821223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86910606 + 86910607.

It is an arithmetic number, because the mean of its divisors is an integer number (86910607).

Almost surely, 2^173821213 is an apocalyptic number.

It is an amenable number.

173821213 is a deficient number, since it is larger than the sum of its proper divisors (1).

173821213 is an equidigital number, since it uses as much as digits as its factorization.

173821213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 28.

The square root of 173821213 is about 13184.1273127955. The cubic root of 173821213 is about 558.0857396202.

Adding to 173821213 its reverse (312128371), we get a palindrome (485949584).

It can be divided in two parts, 17 and 3821213, that added together give a triangular number (3821230 = T₂₇₆₄).

The spelling of 173821213 in words is "one hundred seventy-three million, eight hundred twenty-one thousand, two hundred thirteen".