28155641 has 2 divisors, whose sum is σ = 28155642. Its totient is φ = 28155640.

The previous prime is 28155613. The next prime is 28155649. The reversal of 28155641 is 14655182.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17397241 + 10758400 = 4171^2 + 3280^2 .

It is a cyclic number.

It is not a de Polignac number, because 28155641 - 2¹⁰ = 28154617 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 28155598 and 28155607.

It is not a weakly prime, because it can be changed into another prime (28155649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14077820 + 14077821.

It is an arithmetic number, because the mean of its divisors is an integer number (14077821).

Almost surely, 2^28155641 is an apocalyptic number.

It is an amenable number.

28155641 is a deficient number, since it is larger than the sum of its proper divisors (1).

28155641 is an equidigital number, since it uses as much as digits as its factorization.

28155641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9600, while the sum is 32.

The square root of 28155641 is about 5306.1889336887. The cubic root of 28155641 is about 304.2204980681.

The spelling of 28155641 in words is "twenty-eight million, one hundred fifty-five thousand, six hundred forty-one".