7128765 has 72 divisors (see below), whose sum is σ = 14885208. Its totient is φ = 3144960.

The previous prime is 7128761. The next prime is 7128767. The reversal of 7128765 is 5678217.

It can be written as a sum of positive squares in 4 ways, for example, as 127449 + 7001316 = 357^2 + 2646^2 .

It is not a de Polignac number, because 7128765 - 2² = 7128761 is a prime.

7128765 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7128761) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 116835 + ... + 116895.

It is an arithmetic number, because the mean of its divisors is an integer number (206739).

Almost surely, 2^7128765 is an apocalyptic number.

It is an amenable number.

7128765 is an abundant number, since it is smaller than the sum of its proper divisors (7756443).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7128765 is a wasteful number, since it uses less digits than its factorization.

7128765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139 (or 129 counting only the distinct ones).

The product of its digits is 23520, while the sum is 36.

The square root of 7128765 is about 2669.9747189814. The cubic root of 7128765 is about 192.4589444125.

The spelling of 7128765 in words is "seven million, one hundred twenty-eight thousand, seven hundred sixty-five".