21221120012001 has 64 divisors (see below), whose sum is σ = 35303631767040. Its totient is φ = 11039538677760.

The previous prime is 21221120011999. The next prime is 21221120012011. The reversal of 21221120012001 is 10021002112212.

It is not a de Polignac number, because 21221120012001 - 2¹ = 21221120011999 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21221120012011) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 568774935 + ... + 568812243.

It is an arithmetic number, because the mean of its divisors is an integer number (551619246360).

Almost surely, 2^{21221120012001} is an apocalyptic number.

21221120012001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21221120012001 is a deficient number, since it is larger than the sum of its proper divisors (14082511755039).

21221120012001 is a wasteful number, since it uses less digits than its factorization.

21221120012001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65946.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21221120012001 its reverse (10021002112212), we get a palindrome (31242122124213).

The spelling of 21221120012001 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twenty million, twelve thousand, one".