7128820 has 12 divisors (see below), whose sum is σ = 14970564. Its totient is φ = 2851520.

The previous prime is 7128817. The next prime is 7128833. The reversal of 7128820 is 288217.

It can be written as a sum of positive squares in 2 ways, for example, as 5354596 + 1774224 = 2314^2 + 1332^2 .

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 178201 + ... + 178240.

It is an arithmetic number, because the mean of its divisors is an integer number (1247547).

Almost surely, 2^7128820 is an apocalyptic number.

It is an amenable number.

7128820 is an abundant number, since it is smaller than the sum of its proper divisors (7841744).

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

7128820 is a wasteful number, since it uses less digits than its factorization.

7128820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 356450 (or 356448 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 7128820 is about 2669.9850186846. The cubic root of 7128820 is about 192.4594393657.

The spelling of 7128820 in words is "seven million, one hundred twenty-eight thousand, eight hundred twenty".