2128440581 has 2 divisors, whose sum is σ = 2128440582. Its totient is φ = 2128440580.

The previous prime is 2128440571. The next prime is 2128440619. The reversal of 2128440581 is 1850448212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2103689956 + 24750625 = 45866^2 + 4975^2 .

It is a cyclic number.

It is not a de Polignac number, because 2128440581 - 2¹⁴ = 2128424197 is a prime.

It is a super-2 number, since 2×2128440581² = 9060518613695235122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2128440521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1064220290 + 1064220291.

It is an arithmetic number, because the mean of its divisors is an integer number (1064220291).

Almost surely, 2^2128440581 is an apocalyptic number.

It is an amenable number.

2128440581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2128440581 is an equidigital number, since it uses as much as digits as its factorization.

2128440581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20480, while the sum is 35.

The square root of 2128440581 is about 46135.0255337526. The cubic root of 2128440581 is about 1286.3342802170.

Adding to 2128440581 its reverse (1850448212), we get a palindrome (3978888793).

The spelling of 2128440581 in words is "two billion, one hundred twenty-eight million, four hundred forty thousand, five hundred eighty-one".