21011102222021 has 8 divisors (see below), whose sum is σ = 21199311006720. Its totient is φ = 20822933259072.

The previous prime is 21011102222003. The next prime is 21011102222069. The reversal of 21011102222021 is 12022220111012.

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 21011102222021 - 2¹⁸ = 21011101959877 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011102225021) 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, 8894951 + ... + 11006468.

It is an arithmetic number, because the mean of its divisors is an integer number (2649913875840).

Almost surely, 2^{21011102222021} is an apocalyptic number.

It is an amenable number.

21011102222021 is a deficient number, since it is larger than the sum of its proper divisors (188208784699).

21011102222021 is a wasteful number, since it uses less digits than its factorization.

21011102222021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19910875.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21011102222021 its reverse (12022220111012), we get a palindrome (33033322333033).

The spelling of 21011102222021 in words is "twenty-one trillion, eleven billion, one hundred two million, two hundred twenty-two thousand, twenty-one".