645163523 has 2 divisors, whose sum is σ = 645163524. Its totient is φ = 645163522.

The previous prime is 645163499. The next prime is 645163573. The reversal of 645163523 is 325361546.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 645163523 - 2¹⁶ = 645097987 is a prime.

It is not a weakly prime, because it can be changed into another prime (645163573) 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, 322581761 + 322581762.

It is an arithmetic number, because the mean of its divisors is an integer number (322581762).

Almost surely, 2^645163523 is an apocalyptic number.

645163523 is a deficient number, since it is larger than the sum of its proper divisors (1).

645163523 is an equidigital number, since it uses as much as digits as its factorization.

645163523 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64800, while the sum is 35.

The square root of 645163523 is about 25400.0693502990. The cubic root of 645163523 is about 864.0852695586.

The spelling of 645163523 in words is "six hundred forty-five million, one hundred sixty-three thousand, five hundred twenty-three".