7128505 has 8 divisors (see below), whose sum is σ = 8926272. Its totient is φ = 5454768.

The previous prime is 7128503. The next prime is 7128509. The reversal of 7128505 is 5058217.

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 7128505 - 2¹ = 7128503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7128503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30879 + ... + 31108.

It is an arithmetic number, because the mean of its divisors is an integer number (1115784).

Almost surely, 2^7128505 is an apocalyptic number.

It is an amenable number.

7128505 is a deficient number, since it is larger than the sum of its proper divisors (1797767).

7128505 is a wasteful number, since it uses less digits than its factorization.

7128505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62015.

The product of its (nonzero) digits is 2800, while the sum is 28.

The square root of 7128505 is about 2669.9260289379. The cubic root of 7128505 is about 192.4566045994.

The spelling of 7128505 in words is "seven million, one hundred twenty-eight thousand, five hundred five".