638941 has 4 divisors (see below), whose sum is σ = 659584. Its totient is φ = 618300.

The previous prime is 638933. The next prime is 638959. The reversal of 638941 is 149836.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 638941 - 2³ = 638933 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31), and also a Moran number because the ratio is a prime number: 20611 = 638941 / (6 + 3 + 8 + 9 + 4 + 1).

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638971) 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, 10275 + ... + 10336.

It is an arithmetic number, because the mean of its divisors is an integer number (164896).

2⁶³⁸⁹⁴¹ is an apocalyptic number.

It is an amenable number.

638941 is a deficient number, since it is larger than the sum of its proper divisors (20643).

638941 is a wasteful number, since it uses less digits than its factorization.

638941 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20642.

The product of its digits is 5184, while the sum is 31.

The square root of 638941 is about 799.3378509742. The cubic root of 638941 is about 86.1298291448.

The spelling of 638941 in words is "six hundred thirty-eight thousand, nine hundred forty-one".