27728417 has 2 divisors, whose sum is σ = 27728418. Its totient is φ = 27728416.

The previous prime is 27728413. The next prime is 27728431. The reversal of 27728417 is 71482772.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19149376 + 8579041 = 4376^2 + 2929^2 .

It is a cyclic number.

It is not a de Polignac number, because 27728417 - 2² = 27728413 is a prime.

It is not a weakly prime, because it can be changed into another prime (27728413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13864208 + 13864209.

It is an arithmetic number, because the mean of its divisors is an integer number (13864209).

Almost surely, 2^27728417 is an apocalyptic number.

It is an amenable number.

27728417 is a deficient number, since it is larger than the sum of its proper divisors (1).

27728417 is an equidigital number, since it uses as much as digits as its factorization.

27728417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43904, while the sum is 38.

The square root of 27728417 is about 5265.7779102427. Note that the first 3 decimals coincide. The cubic root of 27728417 is about 302.6739368048.

The spelling of 27728417 in words is "twenty-seven million, seven hundred twenty-eight thousand, four hundred seventeen".