21002001321120 has 48 divisors (see below), whose sum is σ = 66156304163040. Its totient is φ = 5600533685504.

The previous prime is 21002001321079. The next prime is 21002001321143. The reversal of 21002001321120 is 2112310020012.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21002001321120.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21877084230 + ... + 21877085189.

It is an arithmetic number, because the mean of its divisors is an integer number (1378256336730).

Almost surely, 2^{21002001321120} is an apocalyptic number.

21002001321120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002001321120 is an abundant number, since it is smaller than the sum of its proper divisors (45154302841920).

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

21002001321120 is a wasteful number, since it uses less digits than its factorization.

21002001321120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43754169437 (or 43754169429 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21002001321120 its reverse (2112310020012), we get a palindrome (23114311341132).

The spelling of 21002001321120 in words is "twenty-one trillion, two billion, one million, three hundred twenty-one thousand, one hundred twenty".