20111071 has 2 divisors, whose sum is σ = 20111072. Its totient is φ = 20111070.

The previous prime is 20111053. The next prime is 20111081. The reversal of 20111071 is 17011102.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20111071 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20111011) 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, 10055535 + 10055536.

It is an arithmetic number, because the mean of its divisors is an integer number (10055536).

Almost surely, 2^20111071 is an apocalyptic number.

20111071 is a deficient number, since it is larger than the sum of its proper divisors (1).

20111071 is an equidigital number, since it uses as much as digits as its factorization.

20111071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14, while the sum is 13.

The square root of 20111071 is about 4484.5368768692. The cubic root of 20111071 is about 271.9433227857.

Adding to 20111071 its reverse (17011102), we get a palindrome (37122173).

The spelling of 20111071 in words is "twenty million, one hundred eleven thousand, seventy-one".