281649 has 8 divisors (see below), whose sum is σ = 378112. Its totient is φ = 186480.

The previous prime is 281647. The next prime is 281651. The reversal of 281649 is 946182.

It is an interprime number because it is at equal distance from previous prime (281647) and next prime (281651).

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

It is not a de Polignac number, because 281649 - 2¹ = 281647 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (281641) 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, 459 + ... + 879.

It is an arithmetic number, because the mean of its divisors is an integer number (47264).

2²⁸¹⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

281649 is a deficient number, since it is larger than the sum of its proper divisors (96463).

281649 is a wasteful number, since it uses less digits than its factorization.

281649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 647.

The product of its digits is 3456, while the sum is 30.

The square root of 281649 is about 530.7061333733. The cubic root of 281649 is about 65.5495032024.

The spelling of 281649 in words is "two hundred eighty-one thousand, six hundred forty-nine".