21021021122111 has 8 divisors (see below), whose sum is σ = 21590012702304. Its totient is φ = 20452074588000.

The previous prime is 21021021122089. The next prime is 21021021122113. The reversal of 21021021122111 is 11122112012012.

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 21021021122111 - 2²⁶ = 21020954013247 is a prime.

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 21021021122111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021021122113) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10314515 + ... + 12183236.

It is an arithmetic number, because the mean of its divisors is an integer number (2698751587788).

Almost surely, 2^{21021021122111} is an apocalyptic number.

21021021122111 is a deficient number, since it is larger than the sum of its proper divisors (568991580193).

21021021122111 is a wasteful number, since it uses less digits than its factorization.

21021021122111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22523041.

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

Adding to 21021021122111 its reverse (11122112012012), we get a palindrome (32143133134123).

The spelling of 21021021122111 in words is "twenty-one trillion, twenty-one billion, twenty-one million, one hundred twenty-two thousand, one hundred eleven".