28549621 has 2 divisors, whose sum is σ = 28549622. Its totient is φ = 28549620.

The previous prime is 28549561. The next prime is 28549637. The reversal of 28549621 is 12694582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27447121 + 1102500 = 5239^2 + 1050^2 .

It is a cyclic number.

It is not a de Polignac number, because 28549621 - 2²³ = 20161013 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28549321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14274810 + 14274811.

It is an arithmetic number, because the mean of its divisors is an integer number (14274811).

Almost surely, 2^28549621 is an apocalyptic number.

It is an amenable number.

28549621 is a deficient number, since it is larger than the sum of its proper divisors (1).

28549621 is an equidigital number, since it uses as much as digits as its factorization.

28549621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 37.

The square root of 28549621 is about 5343.1845373335. The cubic root of 28549621 is about 305.6329095077.

The spelling of 28549621 in words is "twenty-eight million, five hundred forty-nine thousand, six hundred twenty-one".