638935 has 8 divisors (see below), whose sum is σ = 836496. Its totient is φ = 464640.

The previous prime is 638933. The next prime is 638959. The reversal of 638935 is 539836.

638935 = T₄₈ + T₄₉ + ... + T₁₅₇.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 638935 - 2¹ = 638933 is a prime.

It is a Duffinian number.

638935 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 638935.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638933) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5754 + ... + 5863.

It is an arithmetic number, because the mean of its divisors is an integer number (104562).

2⁶³⁸⁹³⁵ is an apocalyptic number.

638935 is a deficient number, since it is larger than the sum of its proper divisors (197561).

638935 is a wasteful number, since it uses less digits than its factorization.

638935 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11633.

The product of its digits is 19440, while the sum is 34.

The square root of 638935 is about 799.3340978590. The cubic root of 638935 is about 86.1295595421.

Subtracting from 638935 its reverse (539836), we obtain a palindrome (99099).

It can be divided in two parts, 63 and 8935, that added together give a palindrome (8998).

The spelling of 638935 in words is "six hundred thirty-eight thousand, nine hundred thirty-five".