638535 has 8 divisors (see below), whose sum is σ = 1021680. Its totient is φ = 340544.

The previous prime is 638527. The next prime is 638567. The reversal of 638535 is 535836.

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

It is a cyclic number.

It is not a de Polignac number, because 638535 - 2³ = 638527 is a prime.

638535 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21270 + ... + 21299.

It is an arithmetic number, because the mean of its divisors is an integer number (127710).

2⁶³⁸⁵³⁵ is an apocalyptic number.

638535 is a deficient number, since it is larger than the sum of its proper divisors (383145).

638535 is a wasteful number, since it uses less digits than its factorization.

638535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42577.

The product of its digits is 10800, while the sum is 30.

The square root of 638535 is about 799.0838504187. The cubic root of 638535 is about 86.1115822227. Note that the first 3 decimals are identical.

The spelling of 638535 in words is "six hundred thirty-eight thousand, five hundred thirty-five".