638434 has 8 divisors (see below), whose sum is σ = 999360. Its totient is φ = 305316.

The previous prime is 638431. The next prime is 638437. The reversal of 638434 is 434836.

It is an interprime number because it is at equal distance from previous prime (638431) and next prime (638437).

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

It is a d-powerful number, because it can be written as 6⁶ + 3¹⁰ + 4⁴ + 8 + 3¹² + 4⁵ .

It is not an unprimeable number, because it can be changed into a prime (638431) 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, 6894 + ... + 6985.

It is an arithmetic number, because the mean of its divisors is an integer number (124920).

2⁶³⁸⁴³⁴ is an apocalyptic number.

638434 is a deficient number, since it is larger than the sum of its proper divisors (360926).

638434 is a wasteful number, since it uses less digits than its factorization.

638434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13904.

The product of its digits is 6912, while the sum is 28.

The square root of 638434 is about 799.0206505467. The cubic root of 638434 is about 86.1070417625.

The spelling of 638434 in words is "six hundred thirty-eight thousand, four hundred thirty-four".