20021220210001 has 2 divisors, whose sum is σ = 20021220210002. Its totient is φ = 20021220210000.

The previous prime is 20021220209987. The next prime is 20021220210067. The reversal of 20021220210001 is 10001202212002.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18431222785600 + 1589997424401 = 4293160^2 + 1260951^2 .

It is a cyclic number.

It is not a de Polignac number, because 20021220210001 - 2⁷ = 20021220209873 is a prime.

It is not a weakly prime, because it can be changed into another prime (20021220210401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10010610105000 + 10010610105001.

It is an arithmetic number, because the mean of its divisors is an integer number (10010610105001).

Almost surely, 2^{20021220210001} is an apocalyptic number.

It is an amenable number.

20021220210001 is a deficient number, since it is larger than the sum of its proper divisors (1).

20021220210001 is an equidigital number, since it uses as much as digits as its factorization.

20021220210001 is an odious number, because the sum of its binary digits is odd.

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

Adding to 20021220210001 its reverse (10001202212002), we get a palindrome (30022422422003).

The spelling of 20021220210001 in words is "twenty trillion, twenty-one billion, two hundred twenty million, two hundred ten thousand, one".