640450466489 has 2 divisors, whose sum is σ = 640450466490. Its totient is φ = 640450466488.

The previous prime is 640450466437. The next prime is 640450466543. The reversal of 640450466489 is 984664054046.

640450466489 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 631560805264 + 8889661225 = 794708^2 + 94285^2 .

It is a cyclic number.

It is not a de Polignac number, because 640450466489 - 2³² = 636155499193 is a prime.

It is not a weakly prime, because it can be changed into another prime (640450466989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320225233244 + 320225233245.

It is an arithmetic number, because the mean of its divisors is an integer number (320225233245).

Almost surely, 2^640450466489 is an apocalyptic number.

It is an amenable number.

640450466489 is a deficient number, since it is larger than the sum of its proper divisors (1).

640450466489 is an equidigital number, since it uses as much as digits as its factorization.

640450466489 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19906560, while the sum is 56.

The spelling of 640450466489 in words is "six hundred forty billion, four hundred fifty million, four hundred sixty-six thousand, four hundred eighty-nine".