645529 has 2 divisors, whose sum is σ = 645530. Its totient is φ = 645528.

The previous prime is 645527. The next prime is 645571. The reversal of 645529 is 925546.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 419904 + 225625 = 648^2 + 475^2 .

It is a cyclic number.

It is not a de Polignac number, because 645529 - 2¹ = 645527 is a prime.

Together with 645527, it forms a pair of twin primes.

It is a d-powerful number, because it can be written as 6 + 4³ + 5⁵ + 5⁷ + 2¹⁵ + 9⁶ .

It is a self number, because there is not a number n which added to its sum of digits gives 645529.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 645529.

It is not a weakly prime, because it can be changed into another prime (645521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322764 + 322765.

It is an arithmetic number, because the mean of its divisors is an integer number (322765).

2⁶⁴⁵⁵²⁹ is an apocalyptic number.

It is an amenable number.

645529 is a deficient number, since it is larger than the sum of its proper divisors (1).

645529 is an equidigital number, since it uses as much as digits as its factorization.

645529 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10800, while the sum is 31.

The square root of 645529 is about 803.4481937250. The cubic root of 645529 is about 86.4248403228.

The spelling of 645529 in words is "six hundred forty-five thousand, five hundred twenty-nine".