28114721 has 2 divisors, whose sum is σ = 28114722. Its totient is φ = 28114720.

The previous prime is 28114703. The next prime is 28114747. The reversal of 28114721 is 12741182.

It is an a-pointer prime, because the next prime (28114747) can be obtained adding 28114721 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19704721 + 8410000 = 4439^2 + 2900^2 .

It is a cyclic number.

It is not a de Polignac number, because 28114721 - 2⁶ = 28114657 is a prime.

It is not a weakly prime, because it can be changed into another prime (28114321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14057360 + 14057361.

It is an arithmetic number, because the mean of its divisors is an integer number (14057361).

Almost surely, 2^28114721 is an apocalyptic number.

It is an amenable number.

28114721 is a deficient number, since it is larger than the sum of its proper divisors (1).

28114721 is an equidigital number, since it uses as much as digits as its factorization.

28114721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 896, while the sum is 26.

The square root of 28114721 is about 5302.3316569223. The cubic root of 28114721 is about 304.0730469951.

The spelling of 28114721 in words is "twenty-eight million, one hundred fourteen thousand, seven hundred twenty-one".