20440321 has 4 divisors (see below), whose sum is σ = 22298544. Its totient is φ = 18582100.

The previous prime is 20440319. The next prime is 20440337. The reversal of 20440321 is 12304402.

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 20440321 - 2¹ = 20440319 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20440295 and 20440304.

It is not an unprimeable number, because it can be changed into a prime (20440361) 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, 929095 + ... + 929116.

It is an arithmetic number, because the mean of its divisors is an integer number (5574636).

Almost surely, 2^20440321 is an apocalyptic number.

It is an amenable number.

20440321 is a deficient number, since it is larger than the sum of its proper divisors (1858223).

20440321 is a wasteful number, since it uses less digits than its factorization.

20440321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1858222.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 20440321 is about 4521.0973225535. The cubic root of 20440321 is about 273.4193441725.

Adding to 20440321 its reverse (12304402), we get a palindrome (32744723).

The spelling of 20440321 in words is "twenty million, four hundred forty thousand, three hundred twenty-one".