640057433 has 2 divisors, whose sum is σ = 640057434. Its totient is φ = 640057432.

The previous prime is 640057423. The next prime is 640057459. The reversal of 640057433 is 334750046.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 547185664 + 92871769 = 23392^2 + 9637^2 .

It is a cyclic number.

It is not a de Polignac number, because 640057433 - 2¹⁶ = 639991897 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 640057433.

It is not a weakly prime, because it can be changed into another prime (640057423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320028716 + 320028717.

It is an arithmetic number, because the mean of its divisors is an integer number (320028717).

Almost surely, 2^640057433 is an apocalyptic number.

It is an amenable number.

640057433 is a deficient number, since it is larger than the sum of its proper divisors (1).

640057433 is an equidigital number, since it uses as much as digits as its factorization.

640057433 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 32.

The square root of 640057433 is about 25299.3563752124. The cubic root of 640057433 is about 861.7996535016.

The spelling of 640057433 in words is "six hundred forty million, fifty-seven thousand, four hundred thirty-three".