21001020122201 has 4 divisors (see below), whose sum is σ = 24001165853952. Its totient is φ = 18000874390452.

The previous prime is 21001020122191. The next prime is 21001020122207. The reversal of 21001020122201 is 10222102010012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21001020122201 - 2³⁰ = 20999946380377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21001020122207) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1500072865865 + ... + 1500072865878.

It is an arithmetic number, because the mean of its divisors is an integer number (6000291463488).

Almost surely, 2^{21001020122201} is an apocalyptic number.

It is an amenable number.

21001020122201 is a deficient number, since it is larger than the sum of its proper divisors (3000145731751).

21001020122201 is an equidigital number, since it uses as much as digits as its factorization.

21001020122201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3000145731750.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21001020122201 its reverse (10222102010012), we get a palindrome (31223122132213).

The spelling of 21001020122201 in words is "twenty-one trillion, one billion, twenty million, one hundred twenty-two thousand, two hundred one".