280668864 has 84 divisors (see below), whose sum is σ = 863873304. Its totient is φ = 80188416.

The previous prime is 280668863. The next prime is 280668877. The reversal of 280668864 is 468866082.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (84).

It is a super-2 number, since 2×280668864² = 157550022438100992, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (280668863) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5509 + ... + 24324.

It is an arithmetic number, because the mean of its divisors is an integer number (10284206).

Almost surely, 2^280668864 is an apocalyptic number.

280668864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

280668864 is an abundant number, since it is smaller than the sum of its proper divisors (583204440).

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

280668864 is a wasteful number, since it uses less digits than its factorization.

280668864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29862 (or 29845 counting only the distinct ones).

The product of its (nonzero) digits is 884736, while the sum is 48.

The square root of 280668864 is about 16753.1747439105. The cubic root of 280668864 is about 654.7337760030.

The spelling of 280668864 in words is "two hundred eighty million, six hundred sixty-eight thousand, eight hundred sixty-four".