2102111878309 has 2 divisors, whose sum is σ = 2102111878310. Its totient is φ = 2102111878308.

The previous prime is 2102111878289. The next prime is 2102111878319. The reversal of 2102111878309 is 9038781112012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2057187804100 + 44924074209 = 1434290^2 + 211953^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102111878309 - 2⁹ = 2102111877797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2102111878319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1051055939154 + 1051055939155.

It is an arithmetic number, because the mean of its divisors is an integer number (1051055939155).

Almost surely, 2^{2102111878309} is an apocalyptic number.

It is an amenable number.

2102111878309 is a deficient number, since it is larger than the sum of its proper divisors (1).

2102111878309 is an equidigital number, since it uses as much as digits as its factorization.

2102111878309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48384, while the sum is 43.

The spelling of 2102111878309 in words is "two trillion, one hundred two billion, one hundred eleven million, eight hundred seventy-eight thousand, three hundred nine".