28312725 has 48 divisors (see below), whose sum is σ = 53964800. Its totient is φ = 12830400.

The previous prime is 28312721. The next prime is 28312727. The reversal of 28312725 is 52721382.

It is not a de Polignac number, because 28312725 - 2² = 28312721 is a prime.

It is a super-2 number, since 2×28312725² = 1603220793851250, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28312692 and 28312701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28312721) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 104340 + ... + 104610.

Almost surely, 2^28312725 is an apocalyptic number.

28312725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28312725 is a deficient number, since it is larger than the sum of its proper divisors (25652075).

28312725 is a wasteful number, since it uses less digits than its factorization.

28312725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490 (or 485 counting only the distinct ones).

The product of its digits is 6720, while the sum is 30.

The square root of 28312725 is about 5320.9703062505. The cubic root of 28312725 is about 304.7852111334.

The spelling of 28312725 in words is "twenty-eight million, three hundred twelve thousand, seven hundred twenty-five".