281044138 has 4 divisors (see below), whose sum is σ = 421566210. Its totient is φ = 140522068.

The previous prime is 281044121. The next prime is 281044147. The reversal of 281044138 is 831440182.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 268533769 + 12510369 = 16387^2 + 3537^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 70261033 + ... + 70261036.

Almost surely, 2^281044138 is an apocalyptic number.

281044138 is a deficient number, since it is larger than the sum of its proper divisors (140522072).

281044138 is a wasteful number, since it uses less digits than its factorization.

281044138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140522071.

The product of its (nonzero) digits is 6144, while the sum is 31.

The square root of 281044138 is about 16764.3710887107. The cubic root of 281044138 is about 655.0254544038.

It can be divided in two parts, 281044 and 138, that added together give a palindrome (281182).

The spelling of 281044138 in words is "two hundred eighty-one million, forty-four thousand, one hundred thirty-eight".