866825811 has 12 divisors (see below), whose sum is σ = 1252684680. Its totient is φ = 577605600.

The previous prime is 866825803. The next prime is 866825831. The reversal of 866825811 is 118528668.

866825811 is a `hidden beast` number, since 8 + 6 + 68 + 2 + 581 + 1 = 666.

It is not a de Polignac number, because 866825811 - 2³ = 866825803 is a prime.

It is not an unprimeable number, because it can be changed into a prime (866825831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2490 + ... + 41711.

It is an arithmetic number, because the mean of its divisors is an integer number (104390390).

Almost surely, 2^866825811 is an apocalyptic number.

866825811 is a deficient number, since it is larger than the sum of its proper divisors (385858869).

866825811 is a wasteful number, since it uses less digits than its factorization.

866825811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46386 (or 46383 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 866825811 is about 29441.9056957935. The cubic root of 866825811 is about 953.4778566193.

The spelling of 866825811 in words is "eight hundred sixty-six million, eight hundred twenty-five thousand, eight hundred eleven".