3128221091 has 2 divisors, whose sum is σ = 3128221092. Its totient is φ = 3128221090.

The previous prime is 3128221081. The next prime is 3128221127. The reversal of 3128221091 is 1901228213.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3128221091 - 2³⁰ = 2054479267 is a prime.

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, 1564110545 + 1564110546.

It is an arithmetic number, because the mean of its divisors is an integer number (1564110546).

Almost surely, 2^3128221091 is an apocalyptic number.

3128221091 is a deficient number, since it is larger than the sum of its proper divisors (1).

3128221091 is an equidigital number, since it uses as much as digits as its factorization.

3128221091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 3128221091 is about 55930.5023310179. The cubic root of 3128221091 is about 1462.5110180678.

The spelling of 3128221091 in words is "three billion, one hundred twenty-eight million, two hundred twenty-one thousand, ninety-one".