28529309 has 2 divisors, whose sum is σ = 28529310. Its totient is φ = 28529308.

The previous prime is 28529261. The next prime is 28529321. The reversal of 28529309 is 90392582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28408900 + 120409 = 5330^2 + 347^2 .

It is a cyclic number.

It is not a de Polignac number, because 28529309 - 2²⁴ = 11752093 is a prime.

It is a super-4 number, since 4×28529309⁴ (a number of 31 digits) contains 4444 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28522309) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14264654 + 14264655.

It is an arithmetic number, because the mean of its divisors is an integer number (14264655).

Almost surely, 2^28529309 is an apocalyptic number.

It is an amenable number.

28529309 is a deficient number, since it is larger than the sum of its proper divisors (1).

28529309 is an equidigital number, since it uses as much as digits as its factorization.

28529309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 28529309 is about 5341.2834599935. The cubic root of 28529309 is about 305.5604101390.

The spelling of 28529309 in words is "twenty-eight million, five hundred twenty-nine thousand, three hundred nine".