21101300201221 has 16 divisors (see below), whose sum is σ = 22433304855600. Its totient is φ = 19848140166144.

The previous prime is 21101300201213. The next prime is 21101300201231. The reversal of 21101300201221 is 12210200310112.

It can be written as a sum of positive squares in 8 ways, for example, as 16544390625 + 21084755810596 = 128625^2 + 4591814^2 .

It is not a de Polignac number, because 21101300201221 - 2³ = 21101300201213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21101300201195 and 21101300201204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21101300201231) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6913101 + ... + 9486493.

It is an arithmetic number, because the mean of its divisors is an integer number (1402081553475).

Almost surely, 2^{21101300201221} is an apocalyptic number.

It is an amenable number.

21101300201221 is a deficient number, since it is larger than the sum of its proper divisors (1332004654379).

21101300201221 is an equidigital number, since it uses as much as digits as its factorization.

21101300201221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2575113 (or 2575079 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21101300201221 its reverse (12210200310112), we get a palindrome (33311500511333).

The spelling of 21101300201221 in words is "twenty-one trillion, one hundred one billion, three hundred million, two hundred one thousand, two hundred twenty-one".