21120001002100 has 288 divisors, whose sum is σ = 61560751859712. Its totient is φ = 6073894080000.

The previous prime is 21120001002097. The next prime is 21120001002161. The reversal of 21120001002100 is 120010002112.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 241297345 + ... + 241384855.

It is an arithmetic number, because the mean of its divisors is an integer number (213752610624).

Almost surely, 2^{21120001002100} is an apocalyptic number.

21120001002100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21120001002100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30780375929856).

21120001002100 is an abundant number, since it is smaller than the sum of its proper divisors (40440750857612).

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

21120001002100 is a wasteful number, since it uses less digits than its factorization.

21120001002100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89967 (or 89960 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21120001002100 its reverse (120010002112), we get a palindrome (21240011004212).

The spelling of 21120001002100 in words is "twenty-one trillion, one hundred twenty billion, one million, two thousand, one hundred".