2105708639 has 2 divisors, whose sum is σ = 2105708640. Its totient is φ = 2105708638.

The previous prime is 2105708513. The next prime is 2105708651. The reversal of 2105708639 is 9368075012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2105708639 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2105708596 and 2105708605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2105708659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1052854319 + 1052854320.

It is an arithmetic number, because the mean of its divisors is an integer number (1052854320).

Almost surely, 2^2105708639 is an apocalyptic number.

2105708639 is a deficient number, since it is larger than the sum of its proper divisors (1).

2105708639 is an equidigital number, since it uses as much as digits as its factorization.

2105708639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 90720, while the sum is 41.

The square root of 2105708639 is about 45888.0010351290. The cubic root of 2105708639 is about 1281.7384903821.

The spelling of 2105708639 in words is "two billion, one hundred five million, seven hundred eight thousand, six hundred thirty-nine".