1020200102021 has 2 divisors, whose sum is σ = 1020200102022. Its totient is φ = 1020200102020.

The previous prime is 1020200102017. The next prime is 1020200102029. The reversal of 1020200102021 is 1202010020201.

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., 676159199521 + 344040902500 = 822289^2 + 586550^2 .

It is an emirp because it is prime and its reverse (1202010020201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1020200102021 - 2² = 1020200102017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1020200101993 and 1020200102011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1020200102029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510100051010 + 510100051011.

It is an arithmetic number, because the mean of its divisors is an integer number (510100051011).

Almost surely, 2^{1020200102021} is an apocalyptic number.

It is an amenable number.

1020200102021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1020200102021 is an equidigital number, since it uses as much as digits as its factorization.

1020200102021 is an odious number, because the sum of its binary digits is odd.

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

Adding to 1020200102021 its reverse (1202010020201), we get a palindrome (2222210122222).

The spelling of 1020200102021 in words is "one trillion, twenty billion, two hundred million, one hundred two thousand, twenty-one".