521145173 has 2 divisors, whose sum is σ = 521145174. Its totient is φ = 521145172.

The previous prime is 521145169. The next prime is 521145181. The reversal of 521145173 is 371541125.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 307020484 + 214124689 = 17522^2 + 14633^2 .

It is a cyclic number.

It is not a de Polignac number, because 521145173 - 2² = 521145169 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521145103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260572586 + 260572587.

It is an arithmetic number, because the mean of its divisors is an integer number (260572587).

Almost surely, 2^521145173 is an apocalyptic number.

It is an amenable number.

521145173 is a deficient number, since it is larger than the sum of its proper divisors (1).

521145173 is an equidigital number, since it uses as much as digits as its factorization.

521145173 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4200, while the sum is 29.

The square root of 521145173 is about 22828.6042718341. The cubic root of 521145173 is about 804.7350300084.

Adding to 521145173 its reverse (371541125), we get a palindrome (892686298).

The spelling of 521145173 in words is "five hundred twenty-one million, one hundred forty-five thousand, one hundred seventy-three".