280642 has 4 divisors (see below), whose sum is σ = 420966. Its totient is φ = 140320.

The previous prime is 280639. The next prime is 280673. The reversal of 280642 is 246082.

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

It can be written as a sum of positive squares in only one way, i.e., 212521 + 68121 = 461^2 + 261^2 .

It is a d-powerful number, because it can be written as 2 + 8³ + 6⁷ + 0 + 4³ + 2⁷ .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 70159 + ... + 70162.

2²⁸⁰⁶⁴² is an apocalyptic number.

280642 is a deficient number, since it is larger than the sum of its proper divisors (140324).

280642 is a wasteful number, since it uses less digits than its factorization.

280642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140323.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 280642 is about 529.7565478595. The cubic root of 280642 is about 65.4712886227.

The spelling of 280642 in words is "two hundred eighty thousand, six hundred forty-two".