21053211121105 has 16 divisors (see below), whose sum is σ = 25551498090240. Its totient is φ = 16650861752448.

The previous prime is 21053211121037. The next prime is 21053211121109. The reversal of 21053211121105 is 50112111235012.

It is a cyclic number.

It is not a de Polignac number, because 21053211121105 - 2²⁷ = 21053076903377 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21053211121105.

It is not an unprimeable number, because it can be changed into a prime (21053211121109) 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 15 ways as a sum of consecutive naturals, for example, 488217 + ... + 6507286.

It is an arithmetic number, because the mean of its divisors is an integer number (1596968630640).

Almost surely, 2^{21053211121105} is an apocalyptic number.

It is an amenable number.

21053211121105 is a deficient number, since it is larger than the sum of its proper divisors (4498286969135).

21053211121105 is an equidigital number, since it uses as much as digits as its factorization.

21053211121105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7002360.

The product of its (nonzero) digits is 600, while the sum is 25.

Adding to 21053211121105 its reverse (50112111235012), we get a palindrome (71165322356117).

The spelling of 21053211121105 in words is "twenty-one trillion, fifty-three billion, two hundred eleven million, one hundred twenty-one thousand, one hundred five".