813228 has 36 divisors (see below), whose sum is σ = 2059848. Its totient is φ = 249600.

The previous prime is 813227. The next prime is 813251. The reversal of 813228 is 822318.

813228 = T₂₃₇ + T₂₃₈ + ... + T₂₆₂.

It is a super-2 number, since 2×813228² = 1322679559968, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 813198 and 813207.

It is not an unprimeable number, because it can be changed into a prime (813221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1828 + ... + 2228.

It is an arithmetic number, because the mean of its divisors is an integer number (57218).

2⁸¹³²²⁸ 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 813228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1029924).

813228 is an abundant number, since it is smaller than the sum of its proper divisors (1246620).

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

813228 is a wasteful number, since it uses less digits than its factorization.

813228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434 (or 419 counting only the distinct ones).

The product of its digits is 768, while the sum is 24.

The square root of 813228 is about 901.7915501933. The cubic root of 813228 is about 93.3406400175.

The spelling of 813228 in words is "eight hundred thirteen thousand, two hundred twenty-eight".