28523639 has 2 divisors, whose sum is σ = 28523640. Its totient is φ = 28523638.

The previous prime is 28523629. The next prime is 28523641. The reversal of 28523639 is 93632582.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28523639 - 2¹⁶ = 28458103 is a prime.

It is a Sophie Germain prime.

Together with 28523641, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28523629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14261819 + 14261820.

It is an arithmetic number, because the mean of its divisors is an integer number (14261820).

Almost surely, 2^28523639 is an apocalyptic number.

28523639 is a deficient number, since it is larger than the sum of its proper divisors (1).

28523639 is an equidigital number, since it uses as much as digits as its factorization.

28523639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 77760, while the sum is 38.

The square root of 28523639 is about 5340.7526623127. The cubic root of 28523639 is about 305.5401661352.

The spelling of 28523639 in words is "twenty-eight million, five hundred twenty-three thousand, six hundred thirty-nine".