280221 has 4 divisors (see below), whose sum is σ = 373632. Its totient is φ = 186812.

The previous prime is 280219. The next prime is 280223. The reversal of 280221 is 122082.

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 an interprime number because it is at equal distance from previous prime (280219) and next prime (280223).

It is a cyclic number.

It is not a de Polignac number, because 280221 - 2¹ = 280219 is a prime.

It is a D-number.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 280221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280223) 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, 46701 + ... + 46706.

It is an arithmetic number, because the mean of its divisors is an integer number (93408).

2²⁸⁰²²¹ is an apocalyptic number.

It is an amenable number.

280221 is a deficient number, since it is larger than the sum of its proper divisors (93411).

280221 is an equidigital number, since it uses as much as digits as its factorization.

280221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93410.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 280221 is about 529.3590463948. The cubic root of 280221 is about 65.4385337167.

The spelling of 280221 in words is "two hundred eighty thousand, two hundred twenty-one".