21010220020201 has 4 divisors (see below), whose sum is σ = 21011330691972. Its totient is φ = 21009109348432.

The previous prime is 21010220020193. The next prime is 21010220020301. The reversal of 21010220020201 is 10202002201012.

It is a happy number.

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 12086712794025 + 8923507226176 = 3476595^2 + 2987224^2 .

It is a cyclic number.

It is not a de Polignac number, because 21010220020201 - 2³ = 21010220020193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21010220020301) 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, 555307510 + ... + 555345343.

It is an arithmetic number, because the mean of its divisors is an integer number (5252832672993).

Almost surely, 2^{21010220020201} is an apocalyptic number.

It is an amenable number.

21010220020201 is a deficient number, since it is larger than the sum of its proper divisors (1110671771).

21010220020201 is a wasteful number, since it uses less digits than its factorization.

21010220020201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1110671770.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21010220020201 its reverse (10202002201012), we get a palindrome (31212222221213).

The spelling of 21010220020201 in words is "twenty-one trillion, ten billion, two hundred twenty million, twenty thousand, two hundred one".