21011112200121 has 16 divisors (see below), whose sum is σ = 28987589366400. Its totient is φ = 13521246415488.

The previous prime is 21011112200107. The next prime is 21011112200159. The reversal of 21011112200121 is 12100221111012.

It is a happy number.

It is not a de Polignac number, because 21011112200121 - 2¹¹ = 21011112198073 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21011112200121.

It is not an unprimeable number, because it can be changed into a prime (21011112200101) 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, 27727981 + ... + 28475658.

It is an arithmetic number, because the mean of its divisors is an integer number (1811724335400).

Almost surely, 2^{21011112200121} is an apocalyptic number.

It is an amenable number.

21011112200121 is a deficient number, since it is larger than the sum of its proper divisors (7976477166279).

21011112200121 is a wasteful number, since it uses less digits than its factorization.

21011112200121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56207968.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21011112200121 its reverse (12100221111012), we get a palindrome (33111333311133).

The spelling of 21011112200121 in words is "twenty-one trillion, eleven billion, one hundred twelve million, two hundred thousand, one hundred twenty-one".