645113123 has 2 divisors, whose sum is σ = 645113124. Its totient is φ = 645113122.

The previous prime is 645113113. The next prime is 645113197. The reversal of 645113123 is 321311546.

645113123 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 645113123 - 2⁴ = 645113107 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 645113092 and 645113101.

It is not a weakly prime, because it can be changed into another prime (645113113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322556561 + 322556562.

It is an arithmetic number, because the mean of its divisors is an integer number (322556562).

Almost surely, 2^645113123 is an apocalyptic number.

645113123 is a deficient number, since it is larger than the sum of its proper divisors (1).

645113123 is an equidigital number, since it uses as much as digits as its factorization.

645113123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 26.

The square root of 645113123 is about 25399.0772076467. The cubic root of 645113123 is about 864.0627682701.

Adding to 645113123 its reverse (321311546), we get a palindrome (966424669).

The spelling of 645113123 in words is "six hundred forty-five million, one hundred thirteen thousand, one hundred twenty-three".