645203113 has 2 divisors, whose sum is σ = 645203114. Its totient is φ = 645203112.

The previous prime is 645203087. The next prime is 645203123. The reversal of 645203113 is 311302546.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 419963049 + 225240064 = 20493^2 + 15008^2 .

It is a cyclic number.

It is not a de Polignac number, because 645203113 - 2²¹ = 643105961 is a prime.

It is not a weakly prime, because it can be changed into another prime (645203123) 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, 322601556 + 322601557.

It is an arithmetic number, because the mean of its divisors is an integer number (322601557).

Almost surely, 2^645203113 is an apocalyptic number.

It is an amenable number.

645203113 is a deficient number, since it is larger than the sum of its proper divisors (1).

645203113 is an equidigital number, since it uses as much as digits as its factorization.

645203113 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 645203113 is about 25400.8486669245. The cubic root of 645203113 is about 864.1029438561.

Adding to 645203113 its reverse (311302546), we get a palindrome (956505659).

The spelling of 645203113 in words is "six hundred forty-five million, two hundred three thousand, one hundred thirteen".