21000010101200 has 180 divisors, whose sum is σ = 54715801463460. Its totient is φ = 7741959413760.

The previous prime is 21000010101073. The next prime is 21000010101221. The reversal of 21000010101200 is 210101000012.

It can be written as a sum of positive squares in 18 ways, for example, as 20382805031824 + 617205069376 = 4514732^2 + 785624^2 .

It is a Harshad number since it is a multiple of its sum of digits (8).

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 35 ways as a sum of consecutive naturals, for example, 43904936 + ... + 44380664.

It is an arithmetic number, because the mean of its divisors is an integer number (303976674797).

Almost surely, 2^{21000010101200} is an apocalyptic number.

21000010101200 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 21000010101200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27357900731730).

21000010101200 is an abundant number, since it is smaller than the sum of its proper divisors (33715791362260).

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

21000010101200 is a wasteful number, since it uses less digits than its factorization.

21000010101200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476426 (or 476402 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 21000010101200 its reverse (210101000012), we get a palindrome (21210111101212).

The spelling of 21000010101200 in words is "twenty-one trillion, ten million, one hundred one thousand, two hundred".