281409993 has 18 divisors (see below), whose sum is σ = 431802254. Its totient is φ = 176569344.

The previous prime is 281409943. The next prime is 281410001. The reversal of 281409993 is 399904182.

It can be written as a sum of positive squares in 3 ways, for example, as 111576969 + 169833024 = 10563^2 + 13032^2 .

It is not a de Polignac number, because 281409993 - 2⁹ = 281409481 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (281409943) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 51496 + ... + 56697.

Almost surely, 2^281409993 is an apocalyptic number.

It is an amenable number.

281409993 is a deficient number, since it is larger than the sum of its proper divisors (150392261).

281409993 is a wasteful number, since it uses less digits than its factorization.

281409993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108233 (or 108213 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 281409993 is about 16775.2792227134. The cubic root of 281409993 is about 655.3095621210.

The spelling of 281409993 in words is "two hundred eighty-one million, four hundred nine thousand, nine hundred ninety-three".