28539557 has 2 divisors, whose sum is σ = 28539558. Its totient is φ = 28539556.

The previous prime is 28539551. The next prime is 28539601. The reversal of 28539557 is 75593582.

It is an a-pointer prime, because the next prime (28539601) can be obtained adding 28539557 to its sum of digits (44).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14394436 + 14145121 = 3794^2 + 3761^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28539557 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 (28539551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14269778 + 14269779.

It is an arithmetic number, because the mean of its divisors is an integer number (14269779).

Almost surely, 2^28539557 is an apocalyptic number.

It is an amenable number.

28539557 is a deficient number, since it is larger than the sum of its proper divisors (1).

28539557 is an equidigital number, since it uses as much as digits as its factorization.

28539557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 378000, while the sum is 44.

The square root of 28539557 is about 5342.2426938506. The cubic root of 28539557 is about 305.5969924973.

The spelling of 28539557 in words is "twenty-eight million, five hundred thirty-nine thousand, five hundred fifty-seven".