638541 has 6 divisors (see below), whose sum is σ = 922350. Its totient is φ = 425688.

The previous prime is 638527. The next prime is 638567. The reversal of 638541 is 145836.

It can be written as a sum of positive squares in only one way, i.e., 594441 + 44100 = 771^2 + 210^2 .

It is not a de Polignac number, because 638541 - 2¹³ = 630349 is a prime.

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638501) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35466 + ... + 35483.

It is an arithmetic number, because the mean of its divisors is an integer number (153725).

2⁶³⁸⁵⁴¹ is an apocalyptic number.

It is an amenable number.

638541 is a deficient number, since it is larger than the sum of its proper divisors (283809).

638541 is a wasteful number, since it uses less digits than its factorization.

638541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70955 (or 70952 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 638541 is about 799.0876047093. The cubic root of 638541 is about 86.1118519380. Note that the first 3 decimals are identical.

The spelling of 638541 in words is "six hundred thirty-eight thousand, five hundred forty-one".