20001220101001 has 2 divisors, whose sum is σ = 20001220101002. Its totient is φ = 20001220101000.

The previous prime is 20001220100993. The next prime is 20001220101131. The reversal of 20001220101001 is 10010102210002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18507642806601 + 1493577294400 = 4302051^2 + 1222120^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001220101001 - 2³ = 20001220100993 is a prime.

It is not a weakly prime, because it can be changed into another prime (20001220101901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000610050500 + 10000610050501.

It is an arithmetic number, because the mean of its divisors is an integer number (10000610050501).

Almost surely, 2^{20001220101001} is an apocalyptic number.

It is an amenable number.

20001220101001 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001220101001 is an equidigital number, since it uses as much as digits as its factorization.

20001220101001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20001220101001 its reverse (10010102210002), we get a palindrome (30011322311003).

The spelling of 20001220101001 in words is "twenty trillion, one billion, two hundred twenty million, one hundred one thousand, one".