28756517 has 2 divisors, whose sum is σ = 28756518. Its totient is φ = 28756516.

The previous prime is 28756477. The next prime is 28756531. The reversal of 28756517 is 71565782.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28718881 + 37636 = 5359^2 + 194^2 .

It is a cyclic number.

It is not a de Polignac number, because 28756517 - 2¹² = 28752421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28756597) by changing a digit.

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 as a sum of consecutive naturals, namely, 14378258 + 14378259.

It is an arithmetic number, because the mean of its divisors is an integer number (14378259).

Almost surely, 2^28756517 is an apocalyptic number.

It is an amenable number.

28756517 is a deficient number, since it is larger than the sum of its proper divisors (1).

28756517 is an equidigital number, since it uses as much as digits as its factorization.

28756517 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 117600, while the sum is 41.

The square root of 28756517 is about 5362.5103263304. The cubic root of 28756517 is about 306.3694293602.

The spelling of 28756517 in words is "twenty-eight million, seven hundred fifty-six thousand, five hundred seventeen".