21212103121103 has 16 divisors (see below), whose sum is σ = 21341710864320. Its totient is φ = 21082896172800.

The previous prime is 21212103121091. The next prime is 21212103121123. The reversal of 21212103121103 is 30112130121212.

It is a cyclic number.

It is not a de Polignac number, because 21212103121103 - 2¹⁰ = 21212103120079 is a prime.

It is a super-3 number, since 3×21212103121103³ (a number of 41 digits) contains 333 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 (21212103121123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 983898638 + ... + 983920196.

It is an arithmetic number, because the mean of its divisors is an integer number (1333856929020).

Almost surely, 2^{21212103121103} is an apocalyptic number.

21212103121103 is a deficient number, since it is larger than the sum of its proper divisors (129607743217).

21212103121103 is a wasteful number, since it uses less digits than its factorization.

21212103121103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30578.

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 21212103121103 its reverse (30112130121212), we get a palindrome (51324233242315).

The spelling of 21212103121103 in words is "twenty-one trillion, two hundred twelve billion, one hundred three million, one hundred twenty-one thousand, one hundred three".