639043 has 2 divisors, whose sum is σ = 639044. Its totient is φ = 639042.

The previous prime is 639011. The next prime is 639049. The reversal of 639043 is 340936.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 639043 - 2⁵ = 639011 is a prime.

639043 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 638999 and 639017.

It is not a weakly prime, because it can be changed into another prime (639049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 319521 + 319522.

It is an arithmetic number, because the mean of its divisors is an integer number (319522).

2⁶³⁹⁰⁴³ is an apocalyptic number.

639043 is a deficient number, since it is larger than the sum of its proper divisors (1).

639043 is an equidigital number, since it uses as much as digits as its factorization.

639043 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 25.

The square root of 639043 is about 799.4016512367. The cubic root of 639043 is about 86.1344121319.

Adding to 639043 its reverse (340936), we get a palindrome (979979).

The spelling of 639043 in words is "six hundred thirty-nine thousand, forty-three".