20828443 has 4 divisors (see below), whose sum is σ = 20927368. Its totient is φ = 20729520.

The previous prime is 20828419. The next prime is 20828449. The reversal of 20828443 is 34482802.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34482802 = 2 ⋅17241401.

It is a cyclic number.

It is not a de Polignac number, because 20828443 - 2⁵ = 20828411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20828449) 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, 49146 + ... + 49567.

It is an arithmetic number, because the mean of its divisors is an integer number (5231842).

Almost surely, 2^20828443 is an apocalyptic number.

20828443 is a deficient number, since it is larger than the sum of its proper divisors (98925).

20828443 is an equidigital number, since it uses as much as digits as its factorization.

20828443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98924.

The product of its (nonzero) digits is 12288, while the sum is 31.

The square root of 20828443 is about 4563.8189052591. The cubic root of 20828443 is about 275.1390723565.

The spelling of 20828443 in words is "twenty million, eight hundred twenty-eight thousand, four hundred forty-three".