163813 has 4 divisors (see below), whose sum is σ = 176428. Its totient is φ = 151200.

The previous prime is 163811. The next prime is 163819. The reversal of 163813 is 318361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 318361 = 241 ⋅1321.

It can be written as a sum of positive squares in 2 ways, for example, as 39204 + 124609 = 198^2 + 353^2 .

It is a cyclic number.

It is not a de Polignac number, because 163813 - 2¹ = 163811 is a prime.

It is a Duffinian number.

163813 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6288 + ... + 6313.

It is an arithmetic number, because the mean of its divisors is an integer number (44107).

2¹⁶³⁸¹³ is an apocalyptic number.

163813 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

163813 is a deficient number, since it is larger than the sum of its proper divisors (12615).

163813 is a wasteful number, since it uses less digits than its factorization.

163813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12614.

The product of its digits is 432, while the sum is 22.

The square root of 163813 is about 404.7381869802. The cubic root of 163813 is about 54.7162243114.

It can be divided in two parts, 16381 and 3, that added together give a 14-th power (16384 = 2¹⁴).

The spelling of 163813 in words is "one hundred sixty-three thousand, eight hundred thirteen".