21201122120221 has 8 divisors (see below), whose sum is σ = 21221042790240. Its totient is φ = 21181209327312.

The previous prime is 21201122120107. The next prime is 21201122120273. The reversal of 21201122120221 is 12202122110212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21201122120221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201122120291) 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 7 ways as a sum of consecutive naturals, for example, 3423151 + ... + 7356643.

It is an arithmetic number, because the mean of its divisors is an integer number (2652630348780).

Almost surely, 2^{21201122120221} is an apocalyptic number.

It is an amenable number.

21201122120221 is a deficient number, since it is larger than the sum of its proper divisors (19920670019).

21201122120221 is a wasteful number, since it uses less digits than its factorization.

21201122120221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3938555.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21201122120221 its reverse (12202122110212), we get a palindrome (33403244230433).

The spelling of 21201122120221 in words is "twenty-one trillion, two hundred one billion, one hundred twenty-two million, one hundred twenty thousand, two hundred twenty-one".