2106666647 has 2 divisors, whose sum is σ = 2106666648. Its totient is φ = 2106666646.

The previous prime is 2106666643. The next prime is 2106666671. The reversal of 2106666647 is 7466666012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2106666647 - 2² = 2106666643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2106666598 and 2106666607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2106666641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1053333323 + 1053333324.

It is an arithmetic number, because the mean of its divisors is an integer number (1053333324).

Almost surely, 2^2106666647 is an apocalyptic number.

2106666647 is a deficient number, since it is larger than the sum of its proper divisors (1).

2106666647 is an equidigital number, since it uses as much as digits as its factorization.

2106666647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 435456, while the sum is 44.

The square root of 2106666647 is about 45898.4383939149. The cubic root of 2106666647 is about 1281.9328397705.

The spelling of 2106666647 in words is "two billion, one hundred six million, six hundred sixty-six thousand, six hundred forty-seven".