638111 has 4 divisors (see below), whose sum is σ = 643872. Its totient is φ = 632352.

The previous prime is 638081. The next prime is 638117. The reversal of 638111 is 111836.

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

It is a cyclic number.

It is not a de Polignac number, because 638111 - 2⁶ = 638047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638117) 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, 2711 + ... + 2936.

It is an arithmetic number, because the mean of its divisors is an integer number (160968).

2⁶³⁸¹¹¹ is an apocalyptic number.

638111 is a deficient number, since it is larger than the sum of its proper divisors (5761).

638111 is a wasteful number, since it uses less digits than its factorization.

638111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5760.

The product of its digits is 144, while the sum is 20.

The square root of 638111 is about 798.8185025398. The cubic root of 638111 is about 86.0925180653.

Adding to 638111 its reverse (111836), we get a palindrome (749947).

The spelling of 638111 in words is "six hundred thirty-eight thousand, one hundred eleven".