28775261 has 2 divisors, whose sum is σ = 28775262. Its totient is φ = 28775260.

The previous prime is 28775239. The next prime is 28775273. The reversal of 28775261 is 16257782.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15452761 + 13322500 = 3931^2 + 3650^2 .

It is a cyclic number.

It is not a de Polignac number, because 28775261 - 2¹⁸ = 28513117 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28775281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14387630 + 14387631.

It is an arithmetic number, because the mean of its divisors is an integer number (14387631).

Almost surely, 2^28775261 is an apocalyptic number.

It is an amenable number.

28775261 is a deficient number, since it is larger than the sum of its proper divisors (1).

28775261 is an equidigital number, since it uses as much as digits as its factorization.

28775261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47040, while the sum is 38.

The square root of 28775261 is about 5364.2577305719. The cubic root of 28775261 is about 306.4359805508.

The spelling of 28775261 in words is "twenty-eight million, seven hundred seventy-five thousand, two hundred sixty-one".