280556 has 6 divisors (see below), whose sum is σ = 490980. Its totient is φ = 140276.

The previous prime is 280549. The next prime is 280561. The reversal of 280556 is 655082.

It is an unprimeable number.

280556 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35066 + ... + 35073.

It is an arithmetic number, because the mean of its divisors is an integer number (81830).

2²⁸⁰⁵⁵⁶ is an apocalyptic number.

It is an amenable number.

280556 is a deficient number, since it is larger than the sum of its proper divisors (210424).

280556 is a wasteful number, since it uses less digits than its factorization.

280556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70143 (or 70141 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 280556 is about 529.6753722800. The cubic root of 280556 is about 65.4646002604.

It can be divided in two parts, 2805 and 56, that multiplied together give a triangular number (157080 = T₅₆₀).

The spelling of 280556 in words is "two hundred eighty thousand, five hundred fifty-six".