28756447 has 2 divisors, whose sum is σ = 28756448. Its totient is φ = 28756446.

The previous prime is 28756391. The next prime is 28756451. The reversal of 28756447 is 74465782.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28756447 - 2⁷ = 28756319 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28756477) 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 as a sum of consecutive naturals, namely, 14378223 + 14378224.

It is an arithmetic number, because the mean of its divisors is an integer number (14378224).

Almost surely, 2^28756447 is an apocalyptic number.

28756447 is a deficient number, since it is larger than the sum of its proper divisors (1).

28756447 is an equidigital number, since it uses as much as digits as its factorization.

28756447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 376320, while the sum is 43.

The square root of 28756447 is about 5362.5037995325. The cubic root of 28756447 is about 306.3691807687.

The spelling of 28756447 in words is "twenty-eight million, seven hundred fifty-six thousand, four hundred forty-seven".