20439529 has 4 divisors (see below), whose sum is σ = 22297680. Its totient is φ = 18581380.

The previous prime is 20439493. The next prime is 20439541. The reversal of 20439529 is 92593402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20439529 - 2⁹ = 20439017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20439494 and 20439503.

It is not an unprimeable number, because it can be changed into a prime (20439569) 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, 929059 + ... + 929080.

It is an arithmetic number, because the mean of its divisors is an integer number (5574420).

Almost surely, 2^20439529 is an apocalyptic number.

It is an amenable number.

20439529 is a deficient number, since it is larger than the sum of its proper divisors (1858151).

20439529 is a wasteful number, since it uses less digits than its factorization.

20439529 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1858150.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 20439529 is about 4521.0097323496. The cubic root of 20439529 is about 273.4158127387.

The spelling of 20439529 in words is "twenty million, four hundred thirty-nine thousand, five hundred twenty-nine".