28639529 has 2 divisors, whose sum is σ = 28639530. Its totient is φ = 28639528.

The previous prime is 28639493. The next prime is 28639547. The reversal of 28639529 is 92593682.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15389929 + 13249600 = 3923^2 + 3640^2 .

It is a cyclic number.

It is not a de Polignac number, because 28639529 - 2¹² = 28635433 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a plaindrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 28639529.

It is not a weakly prime, because it can be changed into another prime (28639549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14319764 + 14319765.

It is an arithmetic number, because the mean of its divisors is an integer number (14319765).

Almost surely, 2^28639529 is an apocalyptic number.

It is an amenable number.

28639529 is a deficient number, since it is larger than the sum of its proper divisors (1).

28639529 is an equidigital number, since it uses as much as digits as its factorization.

28639529 is an evil number, because the sum of its binary digits is even.

The product of its digits is 233280, while the sum is 44.

The square root of 28639529 is about 5351.5912586819. The cubic root of 28639529 is about 305.9534046984.

The spelling of 28639529 in words is "twenty-eight million, six hundred thirty-nine thousand, five hundred twenty-nine".