21112100121 has 32 divisors (see below), whose sum is σ = 32325931008. Its totient is φ = 12006040320.

The previous prime is 21112100101. The next prime is 21112100161. The reversal of 21112100121 is 12100121112.

It is not a de Polignac number, because 21112100121 - 2¹⁷ = 21111969049 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21112100097 and 21112100106.

It is not an unprimeable number, because it can be changed into a prime (21112100101) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3916390 + ... + 3921776.

It is an arithmetic number, because the mean of its divisors is an integer number (1010185344).

Almost surely, 2^21112100121 is an apocalyptic number.

21112100121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21112100121 is a deficient number, since it is larger than the sum of its proper divisors (11213830887).

21112100121 is a wasteful number, since it uses less digits than its factorization.

21112100121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6261.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21112100121 its reverse (12100121112), we get a palindrome (33212221233).

The spelling of 21112100121 in words is "twenty-one billion, one hundred twelve million, one hundred thousand, one hundred twenty-one".