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831820 = 2251119199
BaseRepresentation
bin11001011000101001100
31120021001011
43023011030
5203104240
625455004
710033063
oct3130514
91507034
10831820
11518a60
12341464
13231802
141791da
151166ea
hexcb14c

831820 has 48 divisors (see below), whose sum is σ = 2016000. Its totient is φ = 285120.

The previous prime is 831811. The next prime is 831821. The reversal of 831820 is 28138.

Adding to 831820 its reverse (28138), we get a palindrome (859958).

It can be divided in two parts, 8318 and 20, that added together give a palindrome (8338).

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an Ulam number.

It is a partition number, being equal to the number of ways a set of 59 identical objects can be partitioned into subset.

It is a junction number, because it is equal to n+sod(n) for n = 831791 and 831800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (831821) by changing a digit.

831820 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 15 ways as a sum of consecutive naturals, for example, 4081 + ... + 4279.

It is an arithmetic number, because the mean of its divisors is an integer number (42000).

2831820 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 831820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1008000).

831820 is an abundant number, since it is smaller than the sum of its proper divisors (1184180).

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

831820 is a wasteful number, since it uses less digits than its factorization.

831820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238 (or 236 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 831820 is about 912.0416657149. The cubic root of 831820 is about 94.0466043234.

The spelling of 831820 in words is "eight hundred thirty-one thousand, eight hundred twenty".