28757217 has 16 divisors (see below), whose sum is σ = 41368320. Its totient is φ = 17701632.

The previous prime is 28757207. The next prime is 28757231. The reversal of 28757217 is 71275782.

It is not a de Polignac number, because 28757217 - 2⁸ = 28756961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28757207) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2617 + ... + 8022.

It is an arithmetic number, because the mean of its divisors is an integer number (2585520).

Almost surely, 2^28757217 is an apocalyptic number.

It is an amenable number.

28757217 is a deficient number, since it is larger than the sum of its proper divisors (12611103).

28757217 is a wasteful number, since it uses less digits than its factorization.

28757217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10712.

The product of its digits is 54880, while the sum is 39.

The square root of 28757217 is about 5362.5755938728. The cubic root of 28757217 is about 306.3719152531.

The spelling of 28757217 in words is "twenty-eight million, seven hundred fifty-seven thousand, two hundred seventeen".