21120001011121 has 16 divisors (see below), whose sum is σ = 22727295964800. Its totient is φ = 19576739332480.

The previous prime is 21120001011089. The next prime is 21120001011223. The reversal of 21120001011121 is 12111010002112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21120001011121 - 2⁵ = 21120001011089 is a prime.

It is a super-4 number, since 4×21120001011121⁴ (a number of 54 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21120001015121) 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, 75015895 + ... + 75296908.

It is an arithmetic number, because the mean of its divisors is an integer number (1420455997800).

Almost surely, 2^{21120001011121} is an apocalyptic number.

It is an amenable number.

21120001011121 is a deficient number, since it is larger than the sum of its proper divisors (1607294953679).

21120001011121 is a wasteful number, since it uses less digits than its factorization.

21120001011121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150313016.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21120001011121 its reverse (12111010002112), we get a palindrome (33231011013233).

The spelling of 21120001011121 in words is "twenty-one trillion, one hundred twenty billion, one million, eleven thousand, one hundred twenty-one".