280369 has 4 divisors (see below), whose sum is σ = 282100. Its totient is φ = 278640.

The previous prime is 280351. The next prime is 280373. The reversal of 280369 is 963082.

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 35344 + 245025 = 188^2 + 495^2 .

It is a cyclic number.

It is not a de Polignac number, because 280369 - 2⁵ = 280337 is a prime.

It is a super-2 number, since 2×280369² = 157213552322, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (280339) 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, 594 + ... + 955.

It is an arithmetic number, because the mean of its divisors is an integer number (70525).

2²⁸⁰³⁶⁹ is an apocalyptic number.

It is an amenable number.

280369 is a deficient number, since it is larger than the sum of its proper divisors (1731).

280369 is a wasteful number, since it uses less digits than its factorization.

280369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1730.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 280369 is about 529.4988196399. The cubic root of 280369 is about 65.4500522425.

The spelling of 280369 in words is "two hundred eighty thousand, three hundred sixty-nine".