280123 has 4 divisors (see below), whose sum is σ = 281248. Its totient is φ = 279000.

The previous prime is 280121. The next prime is 280129. The reversal of 280123 is 321082.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 321082 = 2 ⋅160541.

It is a cyclic number.

It is not a de Polignac number, because 280123 - 2¹ = 280121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 280097 and 280106.

It is not an unprimeable number, because it can be changed into a prime (280121) 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, 3 + ... + 748.

It is an arithmetic number, because the mean of its divisors is an integer number (70312).

2²⁸⁰¹²³ is an apocalyptic number.

280123 is a deficient number, since it is larger than the sum of its proper divisors (1125).

280123 is an equidigital number, since it uses as much as digits as its factorization.

280123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1124.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 280123 is about 529.2664735273. The cubic root of 280123 is about 65.4309043527.

The spelling of 280123 in words is "two hundred eighty thousand, one hundred twenty-three".