10111111210021 has 2 divisors, whose sum is σ = 10111111210022. Its totient is φ = 10111111210020.

The previous prime is 10111111209977. The next prime is 10111111210037. The reversal of 10111111210021 is 12001211111101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10084524276996 + 26586933025 = 3175614^2 + 163055^2 .

It is an emirp because it is prime and its reverse (12001211111101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 10111111210021 - 2¹¹ = 10111111207973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 10111111209983 and 10111111210010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10111111210091) 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, 5055555605010 + 5055555605011.

It is an arithmetic number, because the mean of its divisors is an integer number (5055555605011).

Almost surely, 2^{10111111210021} is an apocalyptic number.

It is an amenable number.

10111111210021 is a deficient number, since it is larger than the sum of its proper divisors (1).

10111111210021 is an equidigital number, since it uses as much as digits as its factorization.

10111111210021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 10111111210021 its reverse (12001211111101), we get a palindrome (22112322321122).

The spelling of 10111111210021 in words is "ten trillion, one hundred eleven billion, one hundred eleven million, two hundred ten thousand, twenty-one".