21002102021203 has 4 divisors (see below), whose sum is σ = 21004616348008. Its totient is φ = 20999587694400.

The previous prime is 21002102021189. The next prime is 21002102021227. The reversal of 21002102021203 is 30212020120012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21002102021203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21002102021603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1257150873 + ... + 1257167578.

It is an arithmetic number, because the mean of its divisors is an integer number (5251154087002).

Almost surely, 2^{21002102021203} is an apocalyptic number.

21002102021203 is a deficient number, since it is larger than the sum of its proper divisors (2514326805).

21002102021203 is an equidigital number, since it uses as much as digits as its factorization.

21002102021203 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2514326804.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21002102021203 its reverse (30212020120012), we get a palindrome (51214122141215).

The spelling of 21002102021203 in words is "twenty-one trillion, two billion, one hundred two million, twenty-one thousand, two hundred three".