280901 has 4 divisors (see below), whose sum is σ = 282252. Its totient is φ = 279552.

The previous prime is 280897. The next prime is 280909. The reversal of 280901 is 109082.

It is a Cunningham number, because it is equal to 530²+1.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 109082 = 2 ⋅54541.

It can be written as a sum of positive squares in 2 ways, for example, as 276676 + 4225 = 526^2 + 65^2 .

It is a cyclic number.

It is not a de Polignac number, because 280901 - 2² = 280897 is a prime.

It is a Duffinian number.

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 280901.

It is not an unprimeable number, because it can be changed into a prime (280909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 290 + ... + 803.

It is an arithmetic number, because the mean of its divisors is an integer number (70563).

2²⁸⁰⁹⁰¹ is an apocalyptic number.

It is an amenable number.

280901 is a deficient number, since it is larger than the sum of its proper divisors (1351).

280901 is a wasteful number, since it uses less digits than its factorization.

280901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 280901 is about 530.0009433954. Note that the first 3 decimals coincide. The cubic root of 280901 is about 65.4914232307.

Adding to 280901 its reverse (109082), we get a palindrome (389983).

The spelling of 280901 in words is "two hundred eighty thousand, nine hundred one".