645464497 has 2 divisors, whose sum is σ = 645464498. Its totient is φ = 645464496.

The previous prime is 645464473. The next prime is 645464527. The reversal of 645464497 is 794464546.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 361912576 + 283551921 = 19024^2 + 16839^2 .

It is a cyclic number.

It is not a de Polignac number, because 645464497 - 2²³ = 637075889 is a prime.

It is a Chen prime.

It is equal to p_33569698 and since 645464497 and 33569698 have the same sum of digits, it is a Honaker prime.

It is a zygodrome in base 3.

It is a self number, because there is not a number n which added to its sum of digits gives 645464497.

It is not a weakly prime, because it can be changed into another prime (645464597) 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, 322732248 + 322732249.

It is an arithmetic number, because the mean of its divisors is an integer number (322732249).

Almost surely, 2^645464497 is an apocalyptic number.

It is an amenable number.

645464497 is a deficient number, since it is larger than the sum of its proper divisors (1).

645464497 is an equidigital number, since it uses as much as digits as its factorization.

645464497 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2903040, while the sum is 49.

The square root of 645464497 is about 25405.9933283468. The cubic root of 645464497 is about 864.2196162578.

Adding to 645464497 its sum of digits (49), we get a palindrome (645464546).

The spelling of 645464497 in words is "six hundred forty-five million, four hundred sixty-four thousand, four hundred ninety-seven".