21201212111201 has 2 divisors, whose sum is σ = 21201212111202. Its totient is φ = 21201212111200.

The previous prime is 21201212111173. The next prime is 21201212111227. The reversal of 21201212111201 is 10211121210212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20302242651601 + 898969459600 = 4505801^2 + 948140^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201212111201 - 2²² = 21201207916897 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21201212111201.

It is not a weakly prime, because it can be changed into another prime (21201212119201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600606055600 + 10600606055601.

It is an arithmetic number, because the mean of its divisors is an integer number (10600606055601).

Almost surely, 2^{21201212111201} is an apocalyptic number.

It is an amenable number.

21201212111201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201212111201 is an equidigital number, since it uses as much as digits as its factorization.

21201212111201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21201212111201 its reverse (10211121210212), we get a palindrome (31412333321413).

The spelling of 21201212111201 in words is "twenty-one trillion, two hundred one billion, two hundred twelve million, one hundred eleven thousand, two hundred one".