21101200222021 has 2 divisors, whose sum is σ = 21101200222022. Its totient is φ = 21101200222020.

The previous prime is 21101200221979. The next prime is 21101200222073. The reversal of 21101200222021 is 12022200210112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18911939673796 + 2189260548225 = 4348786^2 + 1479615^2 .

It is a cyclic number.

It is not a de Polignac number, because 21101200222021 - 2¹³ = 21101200213829 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21101200221986 and 21101200222004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21101200223021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550600111010 + 10550600111011.

It is an arithmetic number, because the mean of its divisors is an integer number (10550600111011).

Almost surely, 2^{21101200222021} is an apocalyptic number.

It is an amenable number.

21101200222021 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101200222021 is an equidigital number, since it uses as much as digits as its factorization.

21101200222021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21101200222021 its reverse (12022200210112), we get a palindrome (33123400432133).

The spelling of 21101200222021 in words is "twenty-one trillion, one hundred one billion, two hundred million, two hundred twenty-two thousand, twenty-one".