21002013221004 has 36 divisors (see below), whose sum is σ = 56211270681384. Its totient is φ = 6588866892672.

The previous prime is 21002013220999. The next prime is 21002013221107. The reversal of 21002013221004 is 40012231020012.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

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 11 ways as a sum of consecutive naturals, for example, 17158506922 + ... + 17158508145.

It is an arithmetic number, because the mean of its divisors is an integer number (1561424185594).

Almost surely, 2^{21002013221004} is an apocalyptic number.

It is an amenable number.

21002013221004 is an abundant number, since it is smaller than the sum of its proper divisors (35209257460380).

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

21002013221004 is a wasteful number, since it uses less digits than its factorization.

21002013221004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34317015094 (or 34317015089 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21002013221004 its reverse (40012231020012), we get a palindrome (61014244241016).

The spelling of 21002013221004 in words is "twenty-one trillion, two billion, thirteen million, two hundred twenty-one thousand, four".