639703 has 2 divisors, whose sum is σ = 639704. Its totient is φ = 639702.

The previous prime is 639701. The next prime is 639713. The reversal of 639703 is 307936.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 639703 - 2¹ = 639701 is a prime.

Together with 639701, it forms a pair of twin primes.

639703 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (639701) 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, 319851 + 319852.

It is an arithmetic number, because the mean of its divisors is an integer number (319852).

2⁶³⁹⁷⁰³ is an apocalyptic number.

639703 is a deficient number, since it is larger than the sum of its proper divisors (1).

639703 is an equidigital number, since it uses as much as digits as its factorization.

639703 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3402, while the sum is 28.

The square root of 639703 is about 799.8143534596. The cubic root of 639703 is about 86.1640549740.

The spelling of 639703 in words is "six hundred thirty-nine thousand, seven hundred three".