21031100100321 has 16 divisors (see below), whose sum is σ = 29691074112768. Its totient is φ = 13195935814400.

The previous prime is 21031100100281. The next prime is 21031100100407. The reversal of 21031100100321 is 12300100113012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21031100100321 - 2¹⁴ = 21031100083937 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21031100100321.

It is not an unprimeable number, because it can be changed into a prime (21031100100421) 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, 17502136 + ... + 18665126.

It is an arithmetic number, because the mean of its divisors is an integer number (1855692132048).

Almost surely, 2^{21031100100321} is an apocalyptic number.

It is an amenable number.

21031100100321 is a deficient number, since it is larger than the sum of its proper divisors (8659974012447).

21031100100321 is a wasteful number, since it uses less digits than its factorization.

21031100100321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1517592.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21031100100321 its reverse (12300100113012), we get a palindrome (33331200213333).

The spelling of 21031100100321 in words is "twenty-one trillion, thirty-one billion, one hundred million, one hundred thousand, three hundred twenty-one".