640461300643 has 2 divisors, whose sum is σ = 640461300644. Its totient is φ = 640461300642.

The previous prime is 640461300623. The next prime is 640461300649. The reversal of 640461300643 is 346003164046.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640461300643 - 2¹³ = 640461292451 is a prime.

It is not a weakly prime, because it can be changed into another prime (640461300649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320230650321 + 320230650322.

It is an arithmetic number, because the mean of its divisors is an integer number (320230650322).

Almost surely, 2^640461300643 is an apocalyptic number.

640461300643 is a deficient number, since it is larger than the sum of its proper divisors (1).

640461300643 is an equidigital number, since it uses as much as digits as its factorization.

640461300643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 124416, while the sum is 37.

Adding to 640461300643 its reverse (346003164046), we get a palindrome (986464464689).

The spelling of 640461300643 in words is "six hundred forty billion, four hundred sixty-one million, three hundred thousand, six hundred forty-three".