21020021203 has 2 divisors, whose sum is σ = 21020021204. Its totient is φ = 21020021202.

The previous prime is 21020021177. The next prime is 21020021213. The reversal of 21020021203 is 30212002012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21020021203 - 2³³ = 12430086611 is a prime.

It is not a weakly prime, because it can be changed into another prime (21020021213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510010601 + 10510010602.

It is an arithmetic number, because the mean of its divisors is an integer number (10510010602).

Almost surely, 2^21020021203 is an apocalyptic number.

21020021203 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020021203 is an equidigital number, since it uses as much as digits as its factorization.

21020021203 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 21020021203 its reverse (30212002012), we get a palindrome (51232023215).

The spelling of 21020021203 in words is "twenty-one billion, twenty million, twenty-one thousand, two hundred three".