20013311221 has 2 divisors, whose sum is σ = 20013311222. Its totient is φ = 20013311220.

The previous prime is 20013311207. The next prime is 20013311239. The reversal of 20013311221 is 12211331002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18580688721 + 1432622500 = 136311^2 + 37850^2 .

It is a cyclic number.

It is not a de Polignac number, because 20013311221 - 2⁵ = 20013311189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20013311195 and 20013311204.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20013311261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10006655610 + 10006655611.

It is an arithmetic number, because the mean of its divisors is an integer number (10006655611).

Almost surely, 2^20013311221 is an apocalyptic number.

It is an amenable number.

20013311221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20013311221 is an equidigital number, since it uses as much as digits as its factorization.

20013311221 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 16.

Adding to 20013311221 its reverse (12211331002), we get a palindrome (32224642223).

The spelling of 20013311221 in words is "twenty billion, thirteen million, three hundred eleven thousand, two hundred twenty-one".