21112101010109 has 4 divisors (see below), whose sum is σ = 21112622710560. Its totient is φ = 21111579309660.

The previous prime is 21112101010079. The next prime is 21112101010123. The reversal of 21112101010109 is 90101010121112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21112101010109 - 2²⁸ = 21111832574653 is a prime.

It is a super-2 number, since 2×21112101010109² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112101510109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 260789519 + ... + 260870460.

It is an arithmetic number, because the mean of its divisors is an integer number (5278155677640).

Almost surely, 2^{21112101010109} is an apocalyptic number.

It is an amenable number.

21112101010109 is a deficient number, since it is larger than the sum of its proper divisors (521700451).

21112101010109 is an equidigital number, since it uses as much as digits as its factorization.

21112101010109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 521700450.

The product of its (nonzero) digits is 36, while the sum is 20.

The spelling of 21112101010109 in words is "twenty-one trillion, one hundred twelve billion, one hundred one million, ten thousand, one hundred nine".