866781911 has 2 divisors, whose sum is σ = 866781912. Its totient is φ = 866781910.

The previous prime is 866781871. The next prime is 866781913. The reversal of 866781911 is 119187668.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 866781911 - 2¹⁴ = 866765527 is a prime.

Together with 866781913, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866781913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433390955 + 433390956.

It is an arithmetic number, because the mean of its divisors is an integer number (433390956).

Almost surely, 2^866781911 is an apocalyptic number.

866781911 is a deficient number, since it is larger than the sum of its proper divisors (1).

866781911 is an equidigital number, since it uses as much as digits as its factorization.

866781911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 47.

The square root of 866781911 is about 29441.1601503745. The cubic root of 866781911 is about 953.4617601963.

The spelling of 866781911 in words is "eight hundred sixty-six million, seven hundred eighty-one thousand, nine hundred eleven".