280621 has 8 divisors (see below), whose sum is σ = 310464. Its totient is φ = 251520.

The previous prime is 280613. The next prime is 280627. The reversal of 280621 is 126082.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 280621 - 2³ = 280613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 936 + ... + 1198.

It is an arithmetic number, because the mean of its divisors is an integer number (38808).

2²⁸⁰⁶²¹ is an apocalyptic number.

It is an amenable number.

280621 is a deficient number, since it is larger than the sum of its proper divisors (29843).

280621 is a wasteful number, since it uses less digits than its factorization.

280621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 280621 is about 529.7367270635. The cubic root of 280621 is about 65.4696555440.

The spelling of 280621 in words is "two hundred eighty thousand, six hundred twenty-one".