813888 has 70 divisors (see below), whose sum is σ = 2427986. Its totient is φ = 269568.

The previous prime is 813871. The next prime is 813893. The reversal of 813888 is 888318.

It can be written as a sum of positive squares in only one way, i.e., 627264 + 186624 = 792^2 + 432^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a nialpdrome in base 12.

It is a zygodrome in base 12.

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 813888.

It is an unprimeable number.

813888 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 5106 + ... + 5262.

2⁸¹³⁸⁸⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 813888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1213993).

813888 is an abundant number, since it is smaller than the sum of its proper divisors (1614098).

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

813888 is a wasteful number, since it uses less digits than its factorization.

813888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181 (or 162 counting only the distinct ones).

The product of its digits is 12288, while the sum is 36.

The square root of 813888 is about 902.1574142022. The cubic root of 813888 is about 93.3658843378.

It can be divided in two parts, 81 and 3888, that added together give a square (3969 = 63²).

The spelling of 813888 in words is "eight hundred thirteen thousand, eight hundred eighty-eight".