20211439 has 4 divisors (see below), whose sum is σ = 20467360. Its totient is φ = 19955520.

The previous prime is 20211407. The next prime is 20211461. The reversal of 20211439 is 93411202.

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 20211439 - 2⁵ = 20211407 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211469) 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, 127842 + ... + 127999.

It is an arithmetic number, because the mean of its divisors is an integer number (5116840).

Almost surely, 2^20211439 is an apocalyptic number.

20211439 is a deficient number, since it is larger than the sum of its proper divisors (255921).

20211439 is an equidigital number, since it uses as much as digits as its factorization.

20211439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255920.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 20211439 is about 4495.7134027871. The cubic root of 20211439 is about 272.3949666751.

The spelling of 20211439 in words is "twenty million, two hundred eleven thousand, four hundred thirty-nine".