21211200102100 has 18 divisors (see below), whose sum is σ = 46028304221774. Its totient is φ = 8484480040800.

The previous prime is 21211200102049. The next prime is 21211200102101. The reversal of 21211200102100 is 120100211212.

It can be written as a sum of positive squares in 3 ways, for example, as 2588488418884 + 18622711683216 = 1608878^2 + 4315404^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211200102101) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 106056000411 + ... + 106056000610.

Almost surely, 2^{21211200102100} is an apocalyptic number.

21211200102100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211200102100 is an abundant number, since it is smaller than the sum of its proper divisors (24817104119674).

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

21211200102100 is a wasteful number, since it uses less digits than its factorization.

21211200102100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212112001035 (or 212112001028 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21211200102100 its reverse (120100211212), we get a palindrome (21331300313312).

The spelling of 21211200102100 in words is "twenty-one trillion, two hundred eleven billion, two hundred million, one hundred two thousand, one hundred".