280465 has 4 divisors (see below), whose sum is σ = 336564. Its totient is φ = 224368.

The previous prime is 280463. The next prime is 280487. The reversal of 280465 is 564082.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 80656 + 199809 = 284^2 + 447^2 .

It is a cyclic number.

It is not a de Polignac number, because 280465 - 2¹ = 280463 is a prime.

It is a d-powerful number, because it can be written as 2⁹ + 8 + 4 + 0 + 6⁷ + 5 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (280463) 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, 28042 + ... + 28051.

It is an arithmetic number, because the mean of its divisors is an integer number (84141).

2²⁸⁰⁴⁶⁵ is an apocalyptic number.

It is an amenable number.

280465 is a deficient number, since it is larger than the sum of its proper divisors (56099).

280465 is an equidigital number, since it uses as much as digits as its factorization.

280465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56098.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 280465 is about 529.5894636414. The cubic root of 280465 is about 65.4575215515.

The spelling of 280465 in words is "two hundred eighty thousand, four hundred sixty-five".