3128221081 has 2 divisors, whose sum is σ = 3128221082. Its totient is φ = 3128221080.

The previous prime is 3128221037. The next prime is 3128221091. The reversal of 3128221081 is 1801228213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2704520025 + 423701056 = 52005^2 + 20584^2 .

It is a cyclic number.

It is not a de Polignac number, because 3128221081 - 2⁹ = 3128220569 is a prime.

It is a super-2 number, since 2×3128221081² = 19571534263225617122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (3128221001) 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, 1564110540 + 1564110541.

It is an arithmetic number, because the mean of its divisors is an integer number (1564110541).

Almost surely, 2^3128221081 is an apocalyptic number.

It is an amenable number.

3128221081 is a deficient number, since it is larger than the sum of its proper divisors (1).

3128221081 is an equidigital number, since it uses as much as digits as its factorization.

3128221081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 3128221081 is about 55930.5022416213. The cubic root of 3128221081 is about 1462.5110165094.

Adding to 3128221081 its reverse (1801228213), we get a palindrome (4929449294).

The spelling of 3128221081 in words is "three billion, one hundred twenty-eight million, two hundred twenty-one thousand, eighty-one".