640449503 has 2 divisors, whose sum is σ = 640449504. Its totient is φ = 640449502.

The previous prime is 640449389. The next prime is 640449529. The reversal of 640449503 is 305944046.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 640449503 - 2¹⁶ = 640383967 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640449703) 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, 320224751 + 320224752.

It is an arithmetic number, because the mean of its divisors is an integer number (320224752).

Almost surely, 2^640449503 is an apocalyptic number.

640449503 is a deficient number, since it is larger than the sum of its proper divisors (1).

640449503 is an equidigital number, since it uses as much as digits as its factorization.

640449503 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 640449503 is about 25307.1038050584. The cubic root of 640449503 is about 861.9755839755.

The spelling of 640449503 in words is "six hundred forty million, four hundred forty-nine thousand, five hundred three".