21011031221204 has 48 divisors (see below), whose sum is σ = 40191584057856. Its totient is φ = 9567757363200.

The previous prime is 21011031221203. The next prime is 21011031221209. The reversal of 21011031221204 is 40212213011012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011031221203) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 24093959 + ... + 24950769.

It is an arithmetic number, because the mean of its divisors is an integer number (837324667872).

Almost surely, 2^{21011031221204} is an apocalyptic number.

It is an amenable number.

21011031221204 is a deficient number, since it is larger than the sum of its proper divisors (19180552836652).

21011031221204 is a wasteful number, since it uses less digits than its factorization.

21011031221204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 868496 (or 868494 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21011031221204 its reverse (40212213011012), we get a palindrome (61223244232216).

The spelling of 21011031221204 in words is "twenty-one trillion, eleven billion, thirty-one million, two hundred twenty-one thousand, two hundred four".