21112211112121 has 8 divisors (see below), whose sum is σ = 21128955853824. Its totient is φ = 21095471071920.

The previous prime is 21112211112101. The next prime is 21112211112131. The reversal of 21112211112121 is 12121111221112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21112211112121 - 2²¹ = 21112209014969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21112211112101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7836606 + ... + 10180216.

It is an arithmetic number, because the mean of its divisors is an integer number (2641119481728).

Almost surely, 2^{21112211112121} is an apocalyptic number.

It is an amenable number.

21112211112121 is a deficient number, since it is larger than the sum of its proper divisors (16744741703).

21112211112121 is a wasteful number, since it uses less digits than its factorization.

21112211112121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2350751.

The product of its digits is 32, while the sum is 19.

Adding to 21112211112121 its reverse (12121111221112), we get a palindrome (33233322333233).

The spelling of 21112211112121 in words is "twenty-one trillion, one hundred twelve billion, two hundred eleven million, one hundred twelve thousand, one hundred twenty-one".