21122121002111 has 4 divisors (see below), whose sum is σ = 21122144343672. Its totient is φ = 21122097660552.

The previous prime is 21122121002029. The next prime is 21122121002123. The reversal of 21122121002111 is 11120012122112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21122121002111 - 2¹⁰ = 21122121001087 is a prime.

It is a super-2 number, since 2×21122121002111² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21122121002111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122121002161) 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, 10256261 + ... + 12142286.

It is an arithmetic number, because the mean of its divisors is an integer number (5280536085918).

Almost surely, 2^{21122121002111} is an apocalyptic number.

21122121002111 is a deficient number, since it is larger than the sum of its proper divisors (23341561).

21122121002111 is an equidigital number, since it uses as much as digits as its factorization.

21122121002111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23341560.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21122121002111 its reverse (11120012122112), we get a palindrome (32242133124223).

The spelling of 21122121002111 in words is "twenty-one trillion, one hundred twenty-two billion, one hundred twenty-one million, two thousand, one hundred eleven".