163638 has 12 divisors (see below), whose sum is σ = 354588. Its totient is φ = 54540.

The previous prime is 163637. The next prime is 163643. The reversal of 163638 is 836361.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163633) 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, 4528 + ... + 4563.

It is an arithmetic number, because the mean of its divisors is an integer number (29549).

2¹⁶³⁶³⁸ is an apocalyptic number.

163638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

163638 is an abundant number, since it is smaller than the sum of its proper divisors (190950).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

163638 is a wasteful number, since it uses less digits than its factorization.

163638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9099 (or 9096 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 163638 is about 404.5219400725. The cubic root of 163638 is about 54.6967330805.

Adding to 163638 its reverse (836361), we get a palindrome (999999).

The spelling of 163638 in words is "one hundred sixty-three thousand, six hundred thirty-eight".