5281981 has 4 divisors (see below), whose sum is σ = 5560000. Its totient is φ = 5003964.

The previous prime is 5281979. The next prime is 5281993. The reversal of 5281981 is 1891825.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 5281981 - 2¹ = 5281979 is a prime.

It is a super-2 number, since 2×5281981² = 55798646568722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5281921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138981 + ... + 139018.

It is an arithmetic number, because the mean of its divisors is an integer number (1390000).

Almost surely, 2^5281981 is an apocalyptic number.

It is an amenable number.

5281981 is a deficient number, since it is larger than the sum of its proper divisors (278019).

5281981 is a wasteful number, since it uses less digits than its factorization.

It is an anagram of its base 12 representation: 5281981 = (1928851)₁₂.

5281981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278018.

The product of its digits is 5760, while the sum is 34.

The square root of 5281981 is about 2298.2560779861. The cubic root of 5281981 is about 174.1535285629.

It can be divided in two parts, 52819 and 81, that added together give a square (52900 = 230²).

The spelling of 5281981 in words is "five million, two hundred eighty-one thousand, nine hundred eighty-one".