638471 has 4 divisors (see below), whose sum is σ = 642552. Its totient is φ = 634392.

The previous prime is 638467. The next prime is 638489. The reversal of 638471 is 174836.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 638471 - 2² = 638467 is a prime.

It is a super-3 number, since 3×638471³ = 780808949640483333, which contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 638471.

It is not an unprimeable number, because it can be changed into a prime (638431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1796 + ... + 2121.

It is an arithmetic number, because the mean of its divisors is an integer number (160638).

2⁶³⁸⁴⁷¹ is an apocalyptic number.

638471 is a deficient number, since it is larger than the sum of its proper divisors (4081).

638471 is a wasteful number, since it uses less digits than its factorization.

638471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4080.

The product of its digits is 4032, while the sum is 29.

The square root of 638471 is about 799.0438035552. The cubic root of 638471 is about 86.1087051550.

The spelling of 638471 in words is "six hundred thirty-eight thousand, four hundred seventy-one".