16111111105021 has 2 divisors, whose sum is σ = 16111111105022. Its totient is φ = 16111111105020.

The previous prime is 16111111104941. The next prime is 16111111105039. The reversal of 16111111105021 is 12050111111161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15956941008996 + 154170096025 = 3994614^2 + 392645^2 .

It is a cyclic number.

It is not a de Polignac number, because 16111111105021 - 2²¹ = 16111109007869 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16111111104983 and 16111111105001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16111111105081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8055555552510 + 8055555552511.

It is an arithmetic number, because the mean of its divisors is an integer number (8055555552511).

Almost surely, 2^{16111111105021} is an apocalyptic number.

It is an amenable number.

16111111105021 is a deficient number, since it is larger than the sum of its proper divisors (1).

16111111105021 is an equidigital number, since it uses as much as digits as its factorization.

16111111105021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60, while the sum is 22.

Adding to 16111111105021 its reverse (12050111111161), we get a palindrome (28161222216182).

The spelling of 16111111105021 in words is "sixteen trillion, one hundred eleven billion, one hundred eleven million, one hundred five thousand, twenty-one".