20959439 has 4 divisors (see below), whose sum is σ = 20969160. Its totient is φ = 20949720.

The previous prime is 20959429. The next prime is 20959459. The reversal of 20959439 is 93495902.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20959439 - 2¹² = 20955343 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20959396 and 20959405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20959429) 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, 17 + ... + 6474.

It is an arithmetic number, because the mean of its divisors is an integer number (5242290).

Almost surely, 2^20959439 is an apocalyptic number.

20959439 is a deficient number, since it is larger than the sum of its proper divisors (9721).

20959439 is an equidigital number, since it uses as much as digits as its factorization.

20959439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9720.

The product of its (nonzero) digits is 87480, while the sum is 41.

The square root of 20959439 is about 4578.1479879969. The cubic root of 20959439 is about 275.7146766095.

The spelling of 20959439 in words is "twenty million, nine hundred fifty-nine thousand, four hundred thirty-nine".