20528439 has 4 divisors (see below), whose sum is σ = 27371256. Its totient is φ = 13685624.

The previous prime is 20528429. The next prime is 20528447. The reversal of 20528439 is 93482502.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20528439 - 2⁴ = 20528423 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20528429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3421404 + ... + 3421409.

It is an arithmetic number, because the mean of its divisors is an integer number (6842814).

Almost surely, 2^20528439 is an apocalyptic number.

20528439 is a deficient number, since it is larger than the sum of its proper divisors (6842817).

20528439 is an equidigital number, since it uses as much as digits as its factorization.

20528439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6842816.

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 20528439 is about 4530.8320427930. The cubic root of 20528439 is about 273.8116835208.

The spelling of 20528439 in words is "twenty million, five hundred twenty-eight thousand, four hundred thirty-nine".