28730281 has 2 divisors, whose sum is σ = 28730282. Its totient is φ = 28730280.

The previous prime is 28730267. The next prime is 28730297. The reversal of 28730281 is 18203782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14891881 + 13838400 = 3859^2 + 3720^2 .

It is a cyclic number.

It is not a de Polignac number, because 28730281 - 2⁹ = 28729769 is a prime.

It is a super-2 number, since 2×28730281² = 1650858092677922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28730231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14365140 + 14365141.

It is an arithmetic number, because the mean of its divisors is an integer number (14365141).

Almost surely, 2^28730281 is an apocalyptic number.

It is an amenable number.

28730281 is a deficient number, since it is larger than the sum of its proper divisors (1).

28730281 is an equidigital number, since it uses as much as digits as its factorization.

28730281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 28730281 is about 5360.0635257430. The cubic root of 28730281 is about 306.2762289905.

The spelling of 28730281 in words is "twenty-eight million, seven hundred thirty thousand, two hundred eighty-one".