21202020043 has 2 divisors, whose sum is σ = 21202020044. Its totient is φ = 21202020042.

The previous prime is 21202020041. The next prime is 21202020097. The reversal of 21202020043 is 34002020212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21202020043 - 2¹ = 21202020041 is a prime.

Together with 21202020041, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 21202019999 and 21202020026.

It is not a weakly prime, because it can be changed into another prime (21202020041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601010021 + 10601010022.

It is an arithmetic number, because the mean of its divisors is an integer number (10601010022).

Almost surely, 2^21202020043 is an apocalyptic number.

21202020043 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202020043 is an equidigital number, since it uses as much as digits as its factorization.

21202020043 is an evil number, because the sum of its binary digits is even.

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

Adding to 21202020043 its reverse (34002020212), we get a palindrome (55204040255).

The spelling of 21202020043 in words is "twenty-one billion, two hundred two million, twenty thousand, forty-three".