28305137 has 16 divisors (see below), whose sum is σ = 33318912. Its totient is φ = 23541840.

The previous prime is 28305133. The next prime is 28305143. The reversal of 28305137 is 73150382.

It is not a de Polignac number, because 28305137 - 2² = 28305133 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28305133) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81398 + ... + 81744.

It is an arithmetic number, because the mean of its divisors is an integer number (2082432).

Almost surely, 2^28305137 is an apocalyptic number.

It is an amenable number.

28305137 is a deficient number, since it is larger than the sum of its proper divisors (5013775).

28305137 is a wasteful number, since it uses less digits than its factorization.

28305137 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 668.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 28305137 is about 5320.2572306233. The cubic root of 28305137 is about 304.7579805411.

The spelling of 28305137 in words is "twenty-eight million, three hundred five thousand, one hundred thirty-seven".