20012111971 has 2 divisors, whose sum is σ = 20012111972. Its totient is φ = 20012111970.

The previous prime is 20012111891. The next prime is 20012112017. The reversal of 20012111971 is 17911121002.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20012111971 - 2⁷ = 20012111843 is a prime.

It is not a weakly prime, because it can be changed into another prime (20012141971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10006055985 + 10006055986.

It is an arithmetic number, because the mean of its divisors is an integer number (10006055986).

Almost surely, 2^20012111971 is an apocalyptic number.

20012111971 is a deficient number, since it is larger than the sum of its proper divisors (1).

20012111971 is an equidigital number, since it uses as much as digits as its factorization.

20012111971 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252, while the sum is 25.

Adding to 20012111971 its reverse (17911121002), we get a palindrome (37923232973).

The spelling of 20012111971 in words is "twenty billion, twelve million, one hundred eleven thousand, nine hundred seventy-one".