21121021201000 has 96 divisors (see below), whose sum is σ = 57492281925000. Its totient is φ = 7241492966400.

The previous prime is 21121021200973. The next prime is 21121021201031. The reversal of 21121021201000 is 10212012112.

It can be written as a sum of positive squares in 4 ways, for example, as 11664178461796 + 9456842739204 = 3415286^2 + 3075198^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 215471625 + ... + 215569624.

Almost surely, 2^{21121021201000} is an apocalyptic number.

21121021201000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121021201000 is an abundant number, since it is smaller than the sum of its proper divisors (36371260724000).

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

21121021201000 is a wasteful number, since it uses less digits than its factorization.

21121021201000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431041284 (or 431041263 counting only the distinct ones).

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

Adding to 21121021201000 its reverse (10212012112), we get a palindrome (21131233213112).

The spelling of 21121021201000 in words is "twenty-one trillion, one hundred twenty-one billion, twenty-one million, two hundred one thousand".