1010021021521 has 2 divisors, whose sum is σ = 1010021021522. Its totient is φ = 1010021021520.

The previous prime is 1010021021519. The next prime is 1010021021549. The reversal of 1010021021521 is 1251201200101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 980022781521 + 29998240000 = 989961^2 + 173200^2 .

It is a cyclic number.

It is not a de Polignac number, because 1010021021521 - 2¹ = 1010021021519 is a prime.

Together with 1010021021519, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1010021021495 and 1010021021504.

It is not a weakly prime, because it can be changed into another prime (1010021021621) 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, 505010510760 + 505010510761.

It is an arithmetic number, because the mean of its divisors is an integer number (505010510761).

Almost surely, 2^{1010021021521} is an apocalyptic number.

It is an amenable number.

1010021021521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1010021021521 is an equidigital number, since it uses as much as digits as its factorization.

1010021021521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40, while the sum is 16.

Adding to 1010021021521 its reverse (1251201200101), we get a palindrome (2261222221622).

The spelling of 1010021021521 in words is "one trillion, ten billion, twenty-one million, twenty-one thousand, five hundred twenty-one".