28770281 has 2 divisors, whose sum is σ = 28770282. Its totient is φ = 28770280.

The previous prime is 28770277. The next prime is 28770283. The reversal of 28770281 is 18207782.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27931225 + 839056 = 5285^2 + 916^2 .

It is a cyclic number.

It is not a de Polignac number, because 28770281 - 2² = 28770277 is a prime.

It is a super-2 number, since 2×28770281² = 1655458137637922, which contains 22 as substring.

Together with 28770283, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28770283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14385140 + 14385141.

It is an arithmetic number, because the mean of its divisors is an integer number (14385141).

Almost surely, 2^28770281 is an apocalyptic number.

It is an amenable number.

28770281 is a deficient number, since it is larger than the sum of its proper divisors (1).

28770281 is an equidigital number, since it uses as much as digits as its factorization.

28770281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12544, while the sum is 35.

The square root of 28770281 is about 5363.7935269732. The cubic root of 28770281 is about 306.4183017164.

The spelling of 28770281 in words is "twenty-eight million, seven hundred seventy thousand, two hundred eighty-one".