280399 has 8 divisors (see below), whose sum is σ = 328608. Its totient is φ = 234240.

The previous prime is 280373. The next prime is 280409. The reversal of 280399 is 993082.

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 a de Polignac number, because none of the positive numbers 2^k-280399 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 280399.

It is a congruent 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 7 ways as a sum of consecutive naturals, for example, 202 + ... + 775.

It is an arithmetic number, because the mean of its divisors is an integer number (41076).

2²⁸⁰³⁹⁹ is an apocalyptic number.

280399 is a deficient number, since it is larger than the sum of its proper divisors (48209).

280399 is an equidigital number, since it uses as much as digits as its factorization.

280399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1025.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 280399 is about 529.5271475571. The cubic root of 280399 is about 65.4523865847.

The spelling of 280399 in words is "two hundred eighty thousand, three hundred ninety-nine".