281808648 has 48 divisors (see below), whose sum is σ = 832618800. Its totient is φ = 85396320.

The previous prime is 281808601. The next prime is 281808649. The reversal of 281808648 is 846808182.

It is a happy number.

It is a super-2 number, since 2×281808648² = 158832228175175808, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (281808649) 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, 177118 + ... + 178701.

It is an arithmetic number, because the mean of its divisors is an integer number (17346225).

Almost surely, 2^281808648 is an apocalyptic number.

It is an amenable number.

281808648 is an abundant number, since it is smaller than the sum of its proper divisors (550810152).

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

281808648 is a wasteful number, since it uses less digits than its factorization.

281808648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355842 (or 355835 counting only the distinct ones).

The product of its (nonzero) digits is 196608, while the sum is 45.

The square root of 281808648 is about 16787.1572340286. The cubic root of 281808648 is about 655.6188607427.

The spelling of 281808648 in words is "two hundred eighty-one million, eight hundred eight thousand, six hundred forty-eight".