2111999971 has 2 divisors, whose sum is σ = 2111999972. Its totient is φ = 2111999970.

The previous prime is 2111999957. The next prime is 2111999977. The reversal of 2111999971 is 1799991112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2111999971 - 2¹³ = 2111991779 is a prime.

It is not a weakly prime, because it can be changed into another prime (2111999977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1055999985 + 1055999986.

It is an arithmetic number, because the mean of its divisors is an integer number (1055999986).

Almost surely, 2^2111999971 is an apocalyptic number.

2111999971 is a deficient number, since it is larger than the sum of its proper divisors (1).

2111999971 is an equidigital number, since it uses as much as digits as its factorization.

2111999971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 91854, while the sum is 49.

The square root of 2111999971 is about 45956.5008567885. The cubic root of 2111999971 is about 1283.0137261260.

The spelling of 2111999971 in words is "two billion, one hundred eleven million, nine hundred ninety-nine thousand, nine hundred seventy-one".