210001210100221 has 4 divisors (see below), whose sum is σ = 210059269603452. Its totient is φ = 209943150596992.

The previous prime is 210001210100179. The next prime is 210001210100327. The reversal of 210001210100221 is 122001012100012.

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 41312936220196 + 168688273880025 = 6427514^2 + 12988005^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210001210100221 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 (210001210160221) 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, 29029746190 + ... + 29029753423.

It is an arithmetic number, because the mean of its divisors is an integer number (52514817400863).

Almost surely, 2^{210001210100221} is an apocalyptic number.

It is an amenable number.

210001210100221 is a deficient number, since it is larger than the sum of its proper divisors (58059503231).

210001210100221 is an equidigital number, since it uses as much as digits as its factorization.

210001210100221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58059503230.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 210001210100221 its reverse (122001012100012), we get a palindrome (332002222200233).

The spelling of 210001210100221 in words is "two hundred ten trillion, one billion, two hundred ten million, one hundred thousand, two hundred twenty-one".