866155478 has 4 divisors (see below), whose sum is σ = 1299233220. Its totient is φ = 433077738.

The previous prime is 866155471. The next prime is 866155513. The reversal of 866155478 is 874551668.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866155471) 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 as a sum of consecutive naturals, namely, 216538868 + ... + 216538871.

It is an arithmetic number, because the mean of its divisors is an integer number (324808305).

Almost surely, 2^866155478 is an apocalyptic number.

866155478 is a deficient number, since it is larger than the sum of its proper divisors (433077742).

866155478 is a wasteful number, since it uses less digits than its factorization.

866155478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 433077741.

The product of its digits is 1612800, while the sum is 50.

The square root of 866155478 is about 29430.5194993225. The cubic root of 866155478 is about 953.2320123409.

The spelling of 866155478 in words is "eight hundred sixty-six million, one hundred fifty-five thousand, four hundred seventy-eight".