645814417 has 2 divisors, whose sum is σ = 645814418. Its totient is φ = 645814416.

The previous prime is 645814399. The next prime is 645814453. The reversal of 645814417 is 714418546.

645814417 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 can be written as a sum of positive squares in only one way, i.e., 645617281 + 197136 = 25409^2 + 444^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645814417 is a prime.

It is a super-2 number, since 2×645814417² = 834152522410099778, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645814417.

It is not a weakly prime, because it can be changed into another prime (645814817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322907208 + 322907209.

It is an arithmetic number, because the mean of its divisors is an integer number (322907209).

Almost surely, 2^645814417 is an apocalyptic number.

It is an amenable number.

645814417 is a deficient number, since it is larger than the sum of its proper divisors (1).

645814417 is an equidigital number, since it uses as much as digits as its factorization.

645814417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 107520, while the sum is 40.

The square root of 645814417 is about 25412.8789592994. The cubic root of 645814417 is about 864.3757586424.

The spelling of 645814417 in words is "six hundred forty-five million, eight hundred fourteen thousand, four hundred seventeen".