280857216 has 64 divisors (see below), whose sum is σ = 764265600. Its totient is φ = 91330560.

The previous prime is 280857193. The next prime is 280857217. The reversal of 280857216 is 612758082.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (280857217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6825 + ... + 24663.

It is an arithmetic number, because the mean of its divisors is an integer number (11941650).

Almost surely, 2^280857216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 280857216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (382132800).

280857216 is an abundant number, since it is smaller than the sum of its proper divisors (483408384).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

280857216 is a wasteful number, since it uses less digits than its factorization.

280857216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17897 (or 17885 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 39.

The square root of 280857216 is about 16758.7951834253. The cubic root of 280857216 is about 654.8802034082.

The spelling of 280857216 in words is "two hundred eighty million, eight hundred fifty-seven thousand, two hundred sixteen".