21212120121101 has 32 divisors (see below), whose sum is σ = 27285901789440. Its totient is φ = 16037427603456.

The previous prime is 21212120121097. The next prime is 21212120121107. The reversal of 21212120121101 is 10112102121212.

It is not a de Polignac number, because 21212120121101 - 2² = 21212120121097 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21212120121101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212120121107) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 41176691 + ... + 41688656.

It is an arithmetic number, because the mean of its divisors is an integer number (852684430920).

Almost surely, 2^{21212120121101} is an apocalyptic number.

It is an amenable number.

21212120121101 is a deficient number, since it is larger than the sum of its proper divisors (6073781668339).

21212120121101 is a wasteful number, since it uses less digits than its factorization.

21212120121101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82865493.

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

Adding to 21212120121101 its reverse (10112102121212), we get a palindrome (31324222242313).

The spelling of 21212120121101 in words is "twenty-one trillion, two hundred twelve billion, one hundred twenty million, one hundred twenty-one thousand, one hundred one".