21121100011121 has 16 divisors (see below), whose sum is σ = 24408843238080. Its totient is φ = 18062434222080.

The previous prime is 21121100011069. The next prime is 21121100011157. The reversal of 21121100011121 is 12111000112112.

It is a cyclic number.

It is not a de Polignac number, because 21121100011121 - 2⁶ = 21121100011057 is a prime.

It is a super-2 number, since 2×21121100011121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21121100011096 and 21121100011105.

It is not an unprimeable number, because it can be changed into a prime (21121100011021) 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, 28049936 + ... + 28793073.

It is an arithmetic number, because the mean of its divisors is an integer number (1525552702380).

Almost surely, 2^{21121100011121} is an apocalyptic number.

It is an amenable number.

21121100011121 is a deficient number, since it is larger than the sum of its proper divisors (3287743226959).

21121100011121 is a wasteful number, since it uses less digits than its factorization.

21121100011121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56845024.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21121100011121 its reverse (12111000112112), we get a palindrome (33232100123233).

The spelling of 21121100011121 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred million, eleven thousand, one hundred twenty-one".