1020021220021 has 2 divisors, whose sum is σ = 1020021220022. Its totient is φ = 1020021220020.

The previous prime is 1020021220019. The next prime is 1020021220039. The reversal of 1020021220021 is 1200221200201.

It is a happy number.

1020021220021 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., 1004082157521 + 15939062500 = 1002039^2 + 126250^2 .

It is a cyclic number.

It is not a de Polignac number, because 1020021220021 - 2¹ = 1020021220019 is a prime.

Together with 1020021220019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1020021219983 and 1020021220010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1020021220091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510010610010 + 510010610011.

It is an arithmetic number, because the mean of its divisors is an integer number (510010610011).

Almost surely, 2^{1020021220021} is an apocalyptic number.

It is an amenable number.

1020021220021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020021220021 is an equidigital number, since it uses as much as digits as its factorization.

1020021220021 is an evil number, because the sum of its binary digits is even.

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

Adding to 1020021220021 its reverse (1200221200201), we get a palindrome (2220242420222).

The spelling of 1020021220021 in words is "one trillion, twenty billion, twenty-one million, two hundred twenty thousand, twenty-one".