21202120121201 has 16 divisors (see below), whose sum is σ = 21373017307200. Its totient is φ = 21031812529728.

The previous prime is 21202120121179. The next prime is 21202120121257. The reversal of 21202120121201 is 10212102120212.

It is a cyclic number.

It is not a de Polignac number, because 21202120121201 - 2⁶ = 21202120121137 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21202120121201.

It is not an unprimeable number, because it can be changed into a prime (21202120121101) 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, 221294015 + ... + 221389803.

It is an arithmetic number, because the mean of its divisors is an integer number (1335813581700).

Almost surely, 2^{21202120121201} is an apocalyptic number.

It is an amenable number.

21202120121201 is a deficient number, since it is larger than the sum of its proper divisors (170897185999).

21202120121201 is a wasteful number, since it uses less digits than its factorization.

21202120121201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98848.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21202120121201 its reverse (10212102120212), we get a palindrome (31414222241413).

The spelling of 21202120121201 in words is "twenty-one trillion, two hundred two billion, one hundred twenty million, one hundred twenty-one thousand, two hundred one".