7128865 has 8 divisors (see below), whose sum is σ = 9057960. Its totient is φ = 5367552.

The previous prime is 7128833. The next prime is 7128907. The reversal of 7128865 is 5688217.

It can be written as a sum of positive squares in 4 ways, for example, as 456976 + 6671889 = 676^2 + 2583^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7128865 - 2⁵ = 7128833 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41850 + ... + 42019.

It is an arithmetic number, because the mean of its divisors is an integer number (1132245).

Almost surely, 2^7128865 is an apocalyptic number.

It is an amenable number.

7128865 is a deficient number, since it is larger than the sum of its proper divisors (1929095).

7128865 is a wasteful number, since it uses less digits than its factorization.

7128865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83891.

The product of its digits is 26880, while the sum is 37.

The square root of 7128865 is about 2669.9934456848. The cubic root of 7128865 is about 192.4598443255.

The spelling of 7128865 in words is "seven million, one hundred twenty-eight thousand, eight hundred sixty-five".