28000025 has 6 divisors (see below), whose sum is σ = 34720062. Its totient is φ = 22400000.

The previous prime is 28000019. The next prime is 28000031. The reversal of 28000025 is 52000082.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28000019) and next prime (28000031).

It can be written as a sum of positive squares in 3 ways, for example, as 6692569 + 21307456 = 2587^2 + 4616^2 .

It is a de Polignac number, because none of the positive numbers 2^k-28000025 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 27999967 and 28000012.

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, 559976 + ... + 560025.

It is an arithmetic number, because the mean of its divisors is an integer number (5786677).

Almost surely, 2^28000025 is an apocalyptic number.

28000025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28000025 is a deficient number, since it is larger than the sum of its proper divisors (6720037).

28000025 is a wasteful number, since it uses less digits than its factorization.

28000025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1120011 (or 1120006 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 28000025 is about 5291.5049844066. The cubic root of 28000025 is about 303.6589875622.

The spelling of 28000025 in words is "twenty-eight million, twenty-five", and thus it is an aban number and an uban number.