7128144891 has 24 divisors (see below), whose sum is σ = 11805457664. Its totient is φ = 4059946800.

The previous prime is 7128144887. The next prime is 7128144893. The reversal of 7128144891 is 1984418217.

7128144891 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 7128144891 - 2² = 7128144887 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7128144893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 164935 + ... + 203616.

Almost surely, 2^7128144891 is an apocalyptic number.

7128144891 is a deficient number, since it is larger than the sum of its proper divisors (4677312773).

7128144891 is a wasteful number, since it uses less digits than its factorization.

7128144891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368871 (or 368868 counting only the distinct ones).

The product of its digits is 129024, while the sum is 45.

The square root of 7128144891 is about 84428.3417520444. The cubic root of 7128144891 is about 1924.5336378322.

The spelling of 7128144891 in words is "seven billion, one hundred twenty-eight million, one hundred forty-four thousand, eight hundred ninety-one".