28425281 has 2 divisors, whose sum is σ = 28425282. Its totient is φ = 28425280.

The previous prime is 28425277. The next prime is 28425283. The reversal of 28425281 is 18252482.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21242881 + 7182400 = 4609^2 + 2680^2 .

It is a cyclic number.

It is not a de Polignac number, because 28425281 - 2² = 28425277 is a prime.

It is a super-2 number, since 2×28425281² = 1615993199857922, which contains 22 as substring.

Together with 28425283, 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 (28425283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14212640 + 14212641.

It is an arithmetic number, because the mean of its divisors is an integer number (14212641).

Almost surely, 2^28425281 is an apocalyptic number.

It is an amenable number.

28425281 is a deficient number, since it is larger than the sum of its proper divisors (1).

28425281 is an equidigital number, since it uses as much as digits as its factorization.

28425281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10240, while the sum is 32.

The square root of 28425281 is about 5331.5364577202. The cubic root of 28425281 is about 305.1885638601.

The spelling of 28425281 in words is "twenty-eight million, four hundred twenty-five thousand, two hundred eighty-one".