2001220061021 has 2 divisors, whose sum is σ = 2001220061022. Its totient is φ = 2001220061020.

The previous prime is 2001220061003. The next prime is 2001220061063. The reversal of 2001220061021 is 1201600221002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1198871704900 + 802348356121 = 1094930^2 + 895739^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2001220061021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2001220061821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1000610030510 + 1000610030511.

It is an arithmetic number, because the mean of its divisors is an integer number (1000610030511).

Almost surely, 2^{2001220061021} is an apocalyptic number.

It is an amenable number.

2001220061021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2001220061021 is an equidigital number, since it uses as much as digits as its factorization.

2001220061021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 2001220061021 its reverse (1201600221002), we get a palindrome (3202820282023).

The spelling of 2001220061021 in words is "two trillion, one billion, two hundred twenty million, sixty-one thousand, twenty-one".