21311030553121 has 8 divisors (see below), whose sum is σ = 21887150711400. Its totient is φ = 20734918098048.

The previous prime is 21311030553083. The next prime is 21311030553151. The reversal of 21311030553121 is 12135503011312.

It can be written as a sum of positive squares in 4 ways, for example, as 16799382677025 + 4511647876096 = 4098705^2 + 2124064^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21311030553121 - 2²⁵ = 21310996998689 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21311030553121.

It is not an unprimeable number, because it can be changed into a prime (21311030553151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3918555 + ... + 7614271.

It is an arithmetic number, because the mean of its divisors is an integer number (2735893838925).

Almost surely, 2^{21311030553121} is an apocalyptic number.

It is an amenable number.

21311030553121 is a deficient number, since it is larger than the sum of its proper divisors (576120158279).

21311030553121 is a wasteful number, since it uses less digits than its factorization.

21311030553121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3851603.

The product of its (nonzero) digits is 2700, while the sum is 28.

Adding to 21311030553121 its reverse (12135503011312), we get a palindrome (33446533564433).

The spelling of 21311030553121 in words is "twenty-one trillion, three hundred eleven billion, thirty million, five hundred fifty-three thousand, one hundred twenty-one".