21112121011021 has 8 divisors (see below), whose sum is σ = 22030489782720. Its totient is φ = 20193789778272.

The previous prime is 21112121010977. The next prime is 21112121011073. The reversal of 21112121011021 is 12011012121112.

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 21112121011021 - 2²¹ = 21112118913869 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21112121010986 and 21112121011004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112121015021) 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 7 ways as a sum of consecutive naturals, for example, 8232451 + ... + 10487968.

It is an arithmetic number, because the mean of its divisors is an integer number (2753811222840).

Almost surely, 2^{21112121011021} is an apocalyptic number.

It is an amenable number.

21112121011021 is a deficient number, since it is larger than the sum of its proper divisors (918368771699).

21112121011021 is a wasteful number, since it uses less digits than its factorization.

21112121011021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18769475.

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

Adding to 21112121011021 its reverse (12011012121112), we get a palindrome (33123133132133).

The spelling of 21112121011021 in words is "twenty-one trillion, one hundred twelve billion, one hundred twenty-one million, eleven thousand, twenty-one".