65439281 has 2 divisors, whose sum is σ = 65439282. Its totient is φ = 65439280.

The previous prime is 65439247. The next prime is 65439289. The reversal of 65439281 is 18293456.

It is a happy number.

65439281 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65286400 + 152881 = 8080^2 + 391^2 .

It is a cyclic number.

It is not a de Polignac number, because 65439281 - 2⁶ = 65439217 is a prime.

It is a super-2 number, since 2×65439281² = 8564598995593922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (65439289) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32719640 + 32719641.

It is an arithmetic number, because the mean of its divisors is an integer number (32719641).

Almost surely, 2^65439281 is an apocalyptic number.

It is an amenable number.

65439281 is a deficient number, since it is larger than the sum of its proper divisors (1).

65439281 is an equidigital number, since it uses as much as digits as its factorization.

65439281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 51840, while the sum is 38.

The square root of 65439281 is about 8089.4549260132. The cubic root of 65439281 is about 402.9763012333.

The spelling of 65439281 in words is "sixty-five million, four hundred thirty-nine thousand, two hundred eighty-one".