2180781671 has 2 divisors, whose sum is σ = 2180781672. Its totient is φ = 2180781670.

The previous prime is 2180781637. The next prime is 2180781683. The reversal of 2180781671 is 1761870812.

2180781671 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2180781671 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2180781371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1090390835 + 1090390836.

It is an arithmetic number, because the mean of its divisors is an integer number (1090390836).

Almost surely, 2^2180781671 is an apocalyptic number.

2180781671 is a deficient number, since it is larger than the sum of its proper divisors (1).

2180781671 is an equidigital number, since it uses as much as digits as its factorization.

2180781671 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 37632, while the sum is 41.

The square root of 2180781671 is about 46698.8401461964. The cubic root of 2180781671 is about 1296.7932146816.

The spelling of 2180781671 in words is "two billion, one hundred eighty million, seven hundred eighty-one thousand, six hundred seventy-one".