640606523399 has 2 divisors, whose sum is σ = 640606523400. Its totient is φ = 640606523398.

The previous prime is 640606523387. The next prime is 640606523429. The reversal of 640606523399 is 993325606046.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 640606523399 - 2¹⁶ = 640606457863 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 640606523399.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640606523299) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320303261699 + 320303261700.

It is an arithmetic number, because the mean of its divisors is an integer number (320303261700).

Almost surely, 2^640606523399 is an apocalyptic number.

640606523399 is a deficient number, since it is larger than the sum of its proper divisors (1).

640606523399 is an equidigital number, since it uses as much as digits as its factorization.

640606523399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6298560, while the sum is 53.

The spelling of 640606523399 in words is "six hundred forty billion, six hundred six million, five hundred twenty-three thousand, three hundred ninety-nine".