20111121210100 has 18 divisors (see below), whose sum is σ = 43641133026134. Its totient is φ = 8044448484000.

The previous prime is 20111121210031. The next prime is 20111121210127. The reversal of 20111121210100 is 101212111102.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 244150621456 + 19866970588644 = 494116^2 + 4457238^2 .

It is a super-3 number, since 3×20111121210100³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 100555605951 + ... + 100555606150.

Almost surely, 2^{20111121210100} is an apocalyptic number.

20111121210100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20111121210100 is an abundant number, since it is smaller than the sum of its proper divisors (23530011816034).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20111121210100 is a wasteful number, since it uses less digits than its factorization.

20111121210100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201111212115 (or 201111212108 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 20111121210100 its reverse (101212111102), we get a palindrome (20212333321202).

The spelling of 20111121210100 in words is "twenty trillion, one hundred eleven billion, one hundred twenty-one million, two hundred ten thousand, one hundred".