645355043 has 2 divisors, whose sum is σ = 645355044. Its totient is φ = 645355042.

The previous prime is 645355033. The next prime is 645355057. The reversal of 645355043 is 340553546.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645355043 is a prime.

It is equal to p_33564248 and since 645355043 and 33564248 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 645354994 and 645355012.

It is not a weakly prime, because it can be changed into another prime (645355033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322677521 + 322677522.

It is an arithmetic number, because the mean of its divisors is an integer number (322677522).

Almost surely, 2^645355043 is an apocalyptic number.

645355043 is a deficient number, since it is larger than the sum of its proper divisors (1).

645355043 is an equidigital number, since it uses as much as digits as its factorization.

645355043 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108000, while the sum is 35.

The square root of 645355043 is about 25403.8391389963. The cubic root of 645355043 is about 864.1707637690.

The spelling of 645355043 in words is "six hundred forty-five million, three hundred fifty-five thousand, forty-three".