28507225 has 6 divisors (see below), whose sum is σ = 35348990. Its totient is φ = 22805760.

The previous prime is 28507217. The next prime is 28507231. The reversal of 28507225 is 52270582.

It can be written as a sum of positive squares in 3 ways, for example, as 2304 + 28504921 = 48^2 + 5339^2 .

It is not a de Polignac number, because 28507225 - 2³ = 28507217 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 570120 + ... + 570169.

Almost surely, 2^28507225 is an apocalyptic number.

28507225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28507225 is a deficient number, since it is larger than the sum of its proper divisors (6841765).

28507225 is a wasteful number, since it uses less digits than its factorization.

28507225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1140299 (or 1140294 counting only the distinct ones).

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 28507225 is about 5339.2157663837. The cubic root of 28507225 is about 305.4815469365.

The spelling of 28507225 in words is "twenty-eight million, five hundred seven thousand, two hundred twenty-five".