639041 has 4 divisors (see below), whose sum is σ = 688212. Its totient is φ = 589872.

The previous prime is 639011. The next prime is 639043. The reversal of 639041 is 140936.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 229441 + 409600 = 479^2 + 640^2 .

It is a cyclic number.

It is not a de Polignac number, because 639041 - 2⁶ = 638977 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 638998 and 639016.

It is not an unprimeable number, because it can be changed into a prime (639043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24566 + ... + 24591.

It is an arithmetic number, because the mean of its divisors is an integer number (172053).

2⁶³⁹⁰⁴¹ is an apocalyptic number.

It is an amenable number.

639041 is a deficient number, since it is larger than the sum of its proper divisors (49171).

639041 is a wasteful number, since it uses less digits than its factorization.

639041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49170.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 639041 is about 799.4004003001. The cubic root of 639041 is about 86.1343222741.

Adding to 639041 its reverse (140936), we get a palindrome (779977).

The spelling of 639041 in words is "six hundred thirty-nine thousand, forty-one".