280421 has 4 divisors (see below), whose sum is σ = 295200. Its totient is φ = 265644.

The previous prime is 280411. The next prime is 280451. The reversal of 280421 is 124082.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 280421 - 2¹⁰ = 279397 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 280421.

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 280421.

It is not an unprimeable number, because it can be changed into a prime (280411) 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, 7361 + ... + 7398.

It is an arithmetic number, because the mean of its divisors is an integer number (73800).

2²⁸⁰⁴²¹ is an apocalyptic number.

It is an amenable number.

280421 is a deficient number, since it is larger than the sum of its proper divisors (14779).

280421 is a wasteful number, since it uses less digits than its factorization.

280421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14778.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 280421 is about 529.5479204000. The cubic root of 280421 is about 65.4540983298.

The spelling of 280421 in words is "two hundred eighty thousand, four hundred twenty-one".