21011022322121 has 4 divisors (see below), whose sum is σ = 22627254808452. Its totient is φ = 19394789835792.

The previous prime is 21011022322099. The next prime is 21011022322139. The reversal of 21011022322121 is 12122322011012.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13457121876025 + 7553900446096 = 3668395^2 + 2748436^2 .

It is a cyclic number.

It is not a de Polignac number, because 21011022322121 - 2¹⁴ = 21011022305737 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21011022322093 and 21011022322102.

It is not an unprimeable number, because it can be changed into a prime (21011022322421) 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, 808116243146 + ... + 808116243171.

It is an arithmetic number, because the mean of its divisors is an integer number (5656813702113).

Almost surely, 2^{21011022322121} is an apocalyptic number.

It is an amenable number.

21011022322121 is a deficient number, since it is larger than the sum of its proper divisors (1616232486331).

21011022322121 is a wasteful number, since it uses less digits than its factorization.

21011022322121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1616232486330.

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21011022322121 its reverse (12122322011012), we get a palindrome (33133344333133).

The spelling of 21011022322121 in words is "twenty-one trillion, eleven billion, twenty-two million, three hundred twenty-two thousand, one hundred twenty-one".