638211 has 8 divisors (see below), whose sum is σ = 972544. Its totient is φ = 364680.

The previous prime is 638201. The next prime is 638233. The reversal of 638211 is 112836.

638211 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 638211 - 2⁵ = 638179 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 30391 = 638211 / (6 + 3 + 8 + 2 + 1 + 1).

It is a Duffinian number.

638211 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (638201) 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, 15175 + ... + 15216.

It is an arithmetic number, because the mean of its divisors is an integer number (121568).

2⁶³⁸²¹¹ is an apocalyptic number.

638211 is a deficient number, since it is larger than the sum of its proper divisors (334333).

638211 is a wasteful number, since it uses less digits than its factorization.

638211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30401.

The product of its digits is 288, while the sum is 21.

The square root of 638211 is about 798.8810925288. The cubic root of 638211 is about 86.0970150897.

The spelling of 638211 in words is "six hundred thirty-eight thousand, two hundred eleven".