28663925 has 12 divisors (see below), whose sum is σ = 35609700. Its totient is φ = 22888320.

The previous prime is 28663891. The next prime is 28663927. The reversal of 28663925 is 52936682.

It can be written as a sum of positive squares in 6 ways, for example, as 4937284 + 23726641 = 2222^2 + 4871^2 .

It is not a de Polignac number, because 28663925 - 2²⁴ = 11886709 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28663927) 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 11 ways as a sum of consecutive naturals, for example, 25679 + ... + 26771.

It is an arithmetic number, because the mean of its divisors is an integer number (2967475).

Almost surely, 2^28663925 is an apocalyptic number.

28663925 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28663925 is a deficient number, since it is larger than the sum of its proper divisors (6945775).

28663925 is a wasteful number, since it uses less digits than its factorization.

28663925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2152 (or 2147 counting only the distinct ones).

The product of its digits is 155520, while the sum is 41.

The square root of 28663925 is about 5353.8700955477. The cubic root of 28663925 is about 306.0402534369.

The spelling of 28663925 in words is "twenty-eight million, six hundred sixty-three thousand, nine hundred twenty-five".