638441 has 4 divisors (see below), whose sum is σ = 642432. Its totient is φ = 634452.

The previous prime is 638437. The next prime is 638453. The reversal of 638441 is 144836.

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 638441 - 2² = 638437 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 638441.

It is not an unprimeable number, because it can be changed into a prime (638431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1745 + ... + 2078.

It is an arithmetic number, because the mean of its divisors is an integer number (160608).

2⁶³⁸⁴⁴¹ is an apocalyptic number.

It is an amenable number.

638441 is a deficient number, since it is larger than the sum of its proper divisors (3991).

638441 is a wasteful number, since it uses less digits than its factorization.

638441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3990.

The product of its digits is 2304, while the sum is 26.

The square root of 638441 is about 799.0250308970. The cubic root of 638441 is about 86.1073564633.

The spelling of 638441 in words is "six hundred thirty-eight thousand, four hundred forty-one".