21202020013 has 2 divisors, whose sum is σ = 21202020014. Its totient is φ = 21202020012.

The previous prime is 21202019983. The next prime is 21202020041. The reversal of 21202020013 is 31002020212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18742157604 + 2459862409 = 136902^2 + 49597^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21202020013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21202019975 and 21202020002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21202020043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601010006 + 10601010007.

It is an arithmetic number, because the mean of its divisors is an integer number (10601010007).

Almost surely, 2^21202020013 is an apocalyptic number.

It is an amenable number.

21202020013 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202020013 is an equidigital number, since it uses as much as digits as its factorization.

21202020013 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 21202020013 its reverse (31002020212), we get a palindrome (52204040225).

The spelling of 21202020013 in words is "twenty-one billion, two hundred two million, twenty thousand, thirteen".