28018729 has 2 divisors, whose sum is σ = 28018730. Its totient is φ = 28018728.

The previous prime is 28018723. The next prime is 28018733. The reversal of 28018729 is 92781082.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23503104 + 4515625 = 4848^2 + 2125^2 .

It is a cyclic number.

It is not a de Polignac number, because 28018729 - 2¹³ = 28010537 is a prime.

It is not a weakly prime, because it can be changed into another prime (28018723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14009364 + 14009365.

It is an arithmetic number, because the mean of its divisors is an integer number (14009365).

Almost surely, 2^28018729 is an apocalyptic number.

It is an amenable number.

28018729 is a deficient number, since it is larger than the sum of its proper divisors (1).

28018729 is an equidigital number, since it uses as much as digits as its factorization.

28018729 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 28018729 is about 5293.2720504429. The cubic root of 28018729 is about 303.7265871865.

The spelling of 28018729 in words is "twenty-eight million, eighteen thousand, seven hundred twenty-nine".