1001002220021 has 2 divisors, whose sum is σ = 1001002220022. Its totient is φ = 1001002220020.

The previous prime is 1001002220017. The next prime is 1001002220033. The reversal of 1001002220021 is 1200222001001.

It is a happy number.

1001002220021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 933513454225 + 67488765796 = 966185^2 + 259786^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001002220021 - 2² = 1001002220017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1001002219984 and 1001002220011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1001002220321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500501110010 + 500501110011.

It is an arithmetic number, because the mean of its divisors is an integer number (500501110011).

Almost surely, 2^{1001002220021} is an apocalyptic number.

It is an amenable number.

1001002220021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1001002220021 is an equidigital number, since it uses as much as digits as its factorization.

1001002220021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 1001002220021 its reverse (1200222001001), we get a palindrome (2201224221022).

The spelling of 1001002220021 in words is "one trillion, one billion, two million, two hundred twenty thousand, twenty-one".