2102102081 has 2 divisors, whose sum is σ = 2102102082. Its totient is φ = 2102102080.

The previous prime is 2102102063. The next prime is 2102102113. The reversal of 2102102081 is 1802012012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1061717056 + 1040385025 = 32584^2 + 32255^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102102081 - 2⁶ = 2102102017 is a prime.

It is a super-2 number, since 2×2102102081² = 8837666317889061122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (2102108081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1051051040 + 1051051041.

It is an arithmetic number, because the mean of its divisors is an integer number (1051051041).

Almost surely, 2^2102102081 is an apocalyptic number.

It is an amenable number.

2102102081 is a deficient number, since it is larger than the sum of its proper divisors (1).

2102102081 is an equidigital number, since it uses as much as digits as its factorization.

2102102081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 17.

The square root of 2102102081 is about 45848.6867968975. The cubic root of 2102102081 is about 1281.0063052173.

Adding to 2102102081 its reverse (1802012012), we get a palindrome (3904114093).

The spelling of 2102102081 in words is "two billion, one hundred two million, one hundred two thousand, eighty-one".