221211100100201 has 4 divisors (see below), whose sum is σ = 234223517753172. Its totient is φ = 208198682447232.

The previous prime is 221211100100161. The next prime is 221211100100231. The reversal of 221211100100201 is 102001001112122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 199138242373225 + 22072857726976 = 14111635^2 + 4698176^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221211100100201 is a prime.

It is a super-2 number, since 2×221211100100201² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (221211100100231) 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, 6506208826460 + ... + 6506208826493.

It is an arithmetic number, because the mean of its divisors is an integer number (58555879438293).

Almost surely, 2^{221211100100201} is an apocalyptic number.

It is an amenable number.

221211100100201 is a deficient number, since it is larger than the sum of its proper divisors (13012417652971).

221211100100201 is a wasteful number, since it uses less digits than its factorization.

221211100100201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13012417652970.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 221211100100201 its reverse (102001001112122), we get a palindrome (323212101212323).

The spelling of 221211100100201 in words is "two hundred twenty-one trillion, two hundred eleven billion, one hundred million, one hundred thousand, two hundred one".