21001120102100 has 18 divisors (see below), whose sum is σ = 45572430621774. Its totient is φ = 8400448040800.

The previous prime is 21001120102057. The next prime is 21001120102111. The reversal of 21001120102100 is 120102110012.

It can be written as a sum of positive squares in 3 ways, for example, as 1015910789776 + 19985209312324 = 1007924^2 + 4470482^2 .

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, 105005600411 + ... + 105005600610.

Almost surely, 2^{21001120102100} is an apocalyptic number.

21001120102100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001120102100 is an abundant number, since it is smaller than the sum of its proper divisors (24571310519674).

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

21001120102100 is a wasteful number, since it uses less digits than its factorization.

21001120102100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210011201035 (or 210011201028 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21001120102100 its reverse (120102110012), we get a palindrome (21121222212112).

The spelling of 21001120102100 in words is "twenty-one trillion, one billion, one hundred twenty million, one hundred two thousand, one hundred".