811280 has 20 divisors (see below), whose sum is σ = 1886412. Its totient is φ = 324480.

The previous prime is 811277. The next prime is 811289. The reversal of 811280 is 82118.

It can be written as a sum of positive squares in 2 ways, for example, as 215296 + 595984 = 464^2 + 772^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a Smith number, since the sum of its digits (20) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (811289) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4991 + ... + 5150.

2⁸¹¹²⁸⁰ is an apocalyptic number.

811280 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

811280 is an abundant number, since it is smaller than the sum of its proper divisors (1075132).

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

811280 is a wasteful number, since it uses less digits than its factorization.

811280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10154 (or 10148 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 811280 is about 900.7108304001. The cubic root of 811280 is about 93.2660512827.

Adding to 811280 its reverse (82118), we get a palindrome (893398).

It can be divided in two parts, 8112 and 80, that added together give a 13-th power (8192 = 2¹³).

The spelling of 811280 in words is "eight hundred eleven thousand, two hundred eighty".