634209 has 4 divisors (see below), whose sum is σ = 845616. Its totient is φ = 422804.

The previous prime is 634199. The next prime is 634211. The reversal of 634209 is 902436.

634209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 634209 - 2⁵ = 634177 is a prime.

It is an Ulam number.

It is a D-number.

It is a Curzon number.

634209 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (634279) 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, 105699 + ... + 105704.

It is an arithmetic number, because the mean of its divisors is an integer number (211404).

2⁶³⁴²⁰⁹ is an apocalyptic number.

It is an amenable number.

634209 is a deficient number, since it is larger than the sum of its proper divisors (211407).

634209 is a wasteful number, since it uses less digits than its factorization.

634209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211406.

The product of its (nonzero) digits is 1296, while the sum is 24.

The square root of 634209 is about 796.3724003254. The cubic root of 634209 is about 85.9166761005.

The spelling of 634209 in words is "six hundred thirty-four thousand, two hundred nine".