7128225 has 36 divisors (see below), whose sum is σ = 13755196. Its totient is φ = 3507840.

The previous prime is 7128223. The next prime is 7128227. The reversal of 7128225 is 5228217.

It is an interprime number because it is at equal distance from previous prime (7128223) and next prime (7128227).

It can be written as a sum of positive squares in 6 ways, for example, as 31329 + 7096896 = 177^2 + 2664^2 .

It is not a de Polignac number, because 7128225 - 2¹ = 7128223 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7128221) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1707 + ... + 4143.

Almost surely, 2^7128225 is an apocalyptic number.

7128225 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

7128225 is a deficient number, since it is larger than the sum of its proper divisors (6626971).

7128225 is a wasteful number, since it uses less digits than its factorization.

7128225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2466 (or 2458 counting only the distinct ones).

The product of its digits is 2240, while the sum is 27.

The square root of 7128225 is about 2669.8735925133. The cubic root of 7128225 is about 192.4540847370.

The spelling of 7128225 in words is "seven million, one hundred twenty-eight thousand, two hundred twenty-five".