645733043 has 2 divisors, whose sum is σ = 645733044. Its totient is φ = 645733042.

The previous prime is 645733037. The next prime is 645733057. The reversal of 645733043 is 340337546.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 645733043 - 2¹² = 645728947 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 645732994 and 645733012.

It is not a weakly prime, because it can be changed into another prime (645733243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322866521 + 322866522.

It is an arithmetic number, because the mean of its divisors is an integer number (322866522).

Almost surely, 2^645733043 is an apocalyptic number.

645733043 is a deficient number, since it is larger than the sum of its proper divisors (1).

645733043 is an equidigital number, since it uses as much as digits as its factorization.

645733043 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90720, while the sum is 35.

The square root of 645733043 is about 25411.2778702685. The cubic root of 645733043 is about 864.3394527184.

The spelling of 645733043 in words is "six hundred forty-five million, seven hundred thirty-three thousand, forty-three".