10002020120021 has 2 divisors, whose sum is σ = 10002020120022. Its totient is φ = 10002020120020.

The previous prime is 10002020119969. The next prime is 10002020120083. The reversal of 10002020120021 is 12002102020001.

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., 9370608711025 + 631411408996 = 3061145^2 + 794614^2 .

It is an emirp because it is prime and its reverse (12002102020001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 10002020120021 - 2²² = 10002015925717 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 10002020119984 and 10002020120011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10002020120321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5001010060010 + 5001010060011.

It is an arithmetic number, because the mean of its divisors is an integer number (5001010060011).

Almost surely, 2^{10002020120021} is an apocalyptic number.

It is an amenable number.

10002020120021 is a deficient number, since it is larger than the sum of its proper divisors (1).

10002020120021 is an equidigital number, since it uses as much as digits as its factorization.

10002020120021 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 10002020120021 its reverse (12002102020001), we get a palindrome (22004122140022).

The spelling of 10002020120021 in words is "ten trillion, two billion, twenty million, one hundred twenty thousand, twenty-one".