28113109 has 2 divisors, whose sum is σ = 28113110. Its totient is φ = 28113108.

The previous prime is 28113091. The next prime is 28113119. The reversal of 28113109 is 90131182.

Together with previous prime (28113091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16990884 + 11122225 = 4122^2 + 3335^2 .

It is a cyclic number.

It is not a de Polignac number, because 28113109 - 2⁵ = 28113077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28113119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14056554 + 14056555.

It is an arithmetic number, because the mean of its divisors is an integer number (14056555).

Almost surely, 2^28113109 is an apocalyptic number.

It is an amenable number.

28113109 is a deficient number, since it is larger than the sum of its proper divisors (1).

28113109 is an equidigital number, since it uses as much as digits as its factorization.

28113109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 28113109 is about 5302.1796461455. The cubic root of 28113109 is about 304.0672353882.

The spelling of 28113109 in words is "twenty-eight million, one hundred thirteen thousand, one hundred nine".