866781871 has 2 divisors, whose sum is σ = 866781872. Its totient is φ = 866781870.

The previous prime is 866781863. The next prime is 866781911. The reversal of 866781871 is 178187668.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 866781871 - 2³ = 866781863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866781821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433390935 + 433390936.

It is an arithmetic number, because the mean of its divisors is an integer number (433390936).

Almost surely, 2^866781871 is an apocalyptic number.

866781871 is a deficient number, since it is larger than the sum of its proper divisors (1).

866781871 is an equidigital number, since it uses as much as digits as its factorization.

866781871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 903168, while the sum is 52.

The square root of 866781871 is about 29441.1594710534. The cubic root of 866781871 is about 953.4617455296.

The spelling of 866781871 in words is "eight hundred sixty-six million, seven hundred eighty-one thousand, eight hundred seventy-one".