28117745 has 16 divisors (see below), whose sum is σ = 35879760. Its totient is φ = 21080064.

The previous prime is 28117717. The next prime is 28117769. The reversal of 28117745 is 54771182.

It can be written as a sum of positive squares in 8 ways, for example, as 323761 + 27793984 = 569^2 + 5272^2 .

It is a cyclic number.

It is not a de Polignac number, because 28117745 - 2⁸ = 28117489 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 24341 + ... + 25469.

It is an arithmetic number, because the mean of its divisors is an integer number (2242485).

Almost surely, 2^28117745 is an apocalyptic number.

It is an amenable number.

28117745 is a deficient number, since it is larger than the sum of its proper divisors (7762015).

28117745 is a wasteful number, since it uses less digits than its factorization.

28117745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1444.

The product of its digits is 15680, while the sum is 35.

The square root of 28117745 is about 5302.6168068228. The cubic root of 28117745 is about 304.0839485667.

It can be divided in two parts, 281177 and 45, that multiplied together give a triangular number (12652965 = T₅₀₃₀).

The spelling of 28117745 in words is "twenty-eight million, one hundred seventeen thousand, seven hundred forty-five".