639563803 has 2 divisors, whose sum is σ = 639563804. Its totient is φ = 639563802.

The previous prime is 639563801. The next prime is 639563861. The reversal of 639563803 is 308365936.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 639563803 - 2¹ = 639563801 is a prime.

Together with 639563801, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 639563803.

It is not a weakly prime, because it can be changed into another prime (639563801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319781901 + 319781902.

It is an arithmetic number, because the mean of its divisors is an integer number (319781902).

Almost surely, 2^639563803 is an apocalyptic number.

639563803 is a deficient number, since it is larger than the sum of its proper divisors (1).

639563803 is an equidigital number, since it uses as much as digits as its factorization.

639563803 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 349920, while the sum is 43.

The square root of 639563803 is about 25289.5987117234. The cubic root of 639563803 is about 861.5780486108.

The spelling of 639563803 in words is "six hundred thirty-nine million, five hundred sixty-three thousand, eight hundred three".