21121001211100 has 36 divisors (see below), whose sum is σ = 52380083005264. Its totient is φ = 7241486129280.

The previous prime is 21121001211097. The next prime is 21121001211113. The reversal of 21121001211100 is 111210012112.

It is a happy number.

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 11 ways as a sum of consecutive naturals, for example, 15086428737 + ... + 15086430136.

Almost surely, 2^{21121001211100} is an apocalyptic number.

21121001211100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121001211100 is an abundant number, since it is smaller than the sum of its proper divisors (31259081794164).

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

21121001211100 is a wasteful number, since it uses less digits than its factorization.

21121001211100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30172858894 (or 30172858887 counting only the distinct ones).

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

Adding to 21121001211100 its reverse (111210012112), we get a palindrome (21232211223212).

The spelling of 21121001211100 in words is "twenty-one trillion, one hundred twenty-one billion, one million, two hundred eleven thousand, one hundred".