21221111001201 has 16 divisors (see below), whose sum is σ = 29076405315264. Its totient is φ = 13757055850944.

The previous prime is 21221111001199. The next prime is 21221111001217. The reversal of 21221111001201 is 10210011112212.

It is a happy number.

It is not a de Polignac number, because 21221111001201 - 2¹ = 21221111001199 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21221111001221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55287906 + ... + 55670411.

It is an arithmetic number, because the mean of its divisors is an integer number (1817275332204).

Almost surely, 2^{21221111001201} is an apocalyptic number.

It is an amenable number.

21221111001201 is a deficient number, since it is larger than the sum of its proper divisors (7855294314063).

21221111001201 is a wasteful number, since it uses less digits than its factorization.

21221111001201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110960080.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21221111001201 its reverse (10210011112212), we get a palindrome (31431122113413).

The spelling of 21221111001201 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred eleven million, one thousand, two hundred one".