280811 has 2 divisors, whose sum is σ = 280812. Its totient is φ = 280810.

The previous prime is 280771. The next prime is 280817. The reversal of 280811 is 118082.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-280811 is a prime.

It is a Chen prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 280811.

It is not a weakly prime, because it can be changed into another prime (280817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140405 + 140406.

It is an arithmetic number, because the mean of its divisors is an integer number (140406).

2²⁸⁰⁸¹¹ is an apocalyptic number.

280811 is a deficient number, since it is larger than the sum of its proper divisors (1).

280811 is an equidigital number, since it uses as much as digits as its factorization.

280811 is an odious number, because the sum of its binary digits is odd.

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

The square root of 280811 is about 529.9160310842. The cubic root of 280811 is about 65.4844280524.

Adding to 280811 its reverse (118082), we get a palindrome (398893).

It can be divided in two parts, 28081 and 1, that added together give a palindrome (28082).

The spelling of 280811 in words is "two hundred eighty thousand, eight hundred eleven".