21221210010001 has 16 divisors (see below), whose sum is σ = 21793222402560. Its totient is φ = 20656801751040.

The previous prime is 21221210009999. The next prime is 21221210010037. The reversal of 21221210010001 is 10001001212212.

It is a cyclic number.

It is not a de Polignac number, because 21221210010001 - 2¹ = 21221210009999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21291210010001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 299221521 + ... + 299292433.

It is an arithmetic number, because the mean of its divisors is an integer number (1362076400160).

Almost surely, 2^{21221210010001} is an apocalyptic number.

It is an amenable number.

21221210010001 is a deficient number, since it is larger than the sum of its proper divisors (572012392559).

21221210010001 is an equidigital number, since it uses as much as digits as its factorization.

21221210010001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124416.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21221210010001 its reverse (10001001212212), we get a palindrome (31222211222213).

The spelling of 21221210010001 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred ten million, ten thousand, one".