645210793 has 2 divisors, whose sum is σ = 645210794. Its totient is φ = 645210792.

The previous prime is 645210739. The next prime is 645210803. The reversal of 645210793 is 397012546.

Together with previous prime (645210739) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 335732329 + 309478464 = 18323^2 + 17592^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645210793 is a prime.

It is not a weakly prime, because it can be changed into another prime (645219793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322605396 + 322605397.

It is an arithmetic number, because the mean of its divisors is an integer number (322605397).

Almost surely, 2^645210793 is an apocalyptic number.

It is an amenable number.

645210793 is a deficient number, since it is larger than the sum of its proper divisors (1).

645210793 is an equidigital number, since it uses as much as digits as its factorization.

645210793 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 37.

The square root of 645210793 is about 25400.9998425259. Note that the first 3 decimals coincide. The cubic root of 645210793 is about 864.1063723807.

The spelling of 645210793 in words is "six hundred forty-five million, two hundred ten thousand, seven hundred ninety-three".