646440503 has 2 divisors, whose sum is σ = 646440504. Its totient is φ = 646440502.

The previous prime is 646440493. The next prime is 646440511. The reversal of 646440503 is 305044646.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646440503 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 646440503.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646440533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323220251 + 323220252.

It is an arithmetic number, because the mean of its divisors is an integer number (323220252).

Almost surely, 2^646440503 is an apocalyptic number.

646440503 is a deficient number, since it is larger than the sum of its proper divisors (1).

646440503 is an equidigital number, since it uses as much as digits as its factorization.

646440503 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34560, while the sum is 32.

The square root of 646440503 is about 25425.1942568784. The cubic root of 646440503 is about 864.6549919952.

The spelling of 646440503 in words is "six hundred forty-six million, four hundred forty thousand, five hundred three".