21020021303 has 2 divisors, whose sum is σ = 21020021304. Its totient is φ = 21020021302.

The previous prime is 21020021299. The next prime is 21020021311. The reversal of 21020021303 is 30312002012.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21020021303 - 2² = 21020021299 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21020021353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510010651 + 10510010652.

It is an arithmetic number, because the mean of its divisors is an integer number (10510010652).

Almost surely, 2^21020021303 is an apocalyptic number.

21020021303 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020021303 is an equidigital number, since it uses as much as digits as its factorization.

21020021303 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 14.

Adding to 21020021303 its reverse (30312002012), we get a palindrome (51332023315).

The spelling of 21020021303 in words is "twenty-one billion, twenty million, twenty-one thousand, three hundred three".