28459021 has 2 divisors, whose sum is σ = 28459022. Its totient is φ = 28459020.

The previous prime is 28459009. The next prime is 28459051. The reversal of 28459021 is 12095482.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25110121 + 3348900 = 5011^2 + 1830^2 .

It is a cyclic number.

It is not a de Polignac number, because 28459021 - 2⁷ = 28458893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28459051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14229510 + 14229511.

It is an arithmetic number, because the mean of its divisors is an integer number (14229511).

Almost surely, 2^28459021 is an apocalyptic number.

It is an amenable number.

28459021 is a deficient number, since it is larger than the sum of its proper divisors (1).

28459021 is an equidigital number, since it uses as much as digits as its factorization.

28459021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 28459021 is about 5334.6997103867. The cubic root of 28459021 is about 305.3092661641.

The spelling of 28459021 in words is "twenty-eight million, four hundred fifty-nine thousand, twenty-one".