21220002222101 has 4 divisors (see below), whose sum is σ = 21620379622572. Its totient is φ = 20819624821632.

The previous prime is 21220002222071. The next prime is 21220002222119. The reversal of 21220002222101 is 10122220002212.

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 14759504076100 + 6460498146001 = 3841810^2 + 2541751^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21220002222101 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 21220002222101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220002222151) 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, 200188700156 + ... + 200188700261.

It is an arithmetic number, because the mean of its divisors is an integer number (5405094905643).

Almost surely, 2^{21220002222101} is an apocalyptic number.

It is an amenable number.

21220002222101 is a deficient number, since it is larger than the sum of its proper divisors (400377400471).

21220002222101 is an equidigital number, since it uses as much as digits as its factorization.

21220002222101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400377400470.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21220002222101 its reverse (10122220002212), we get a palindrome (31342222224313).

The spelling of 21220002222101 in words is "twenty-one trillion, two hundred twenty billion, two million, two hundred twenty-two thousand, one hundred one".