21011212200121 has 24 divisors (see below), whose sum is σ = 24946121116224. Its totient is φ = 17542284701760.

The previous prime is 21011212200119. The next prime is 21011212200133. The reversal of 21011212200121 is 12100221211012.

It is not a de Polignac number, because 21011212200121 - 2¹ = 21011212200119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21011212200095 and 21011212200104.

It is not an unprimeable number, because it can be changed into a prime (21011212200151) 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 23 ways as a sum of consecutive naturals, for example, 28320141 + ... + 29052586.

It is an arithmetic number, because the mean of its divisors is an integer number (1039421713176).

Almost surely, 2^{21011212200121} is an apocalyptic number.

It is an amenable number.

21011212200121 is a deficient number, since it is larger than the sum of its proper divisors (3934908916103).

21011212200121 is a wasteful number, since it uses less digits than its factorization.

21011212200121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57372961 (or 57372948 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21011212200121 its reverse (12100221211012), we get a palindrome (33111433411133).

The spelling of 21011212200121 in words is "twenty-one trillion, eleven billion, two hundred twelve million, two hundred thousand, one hundred twenty-one".