866481978 has 8 divisors (see below), whose sum is σ = 1732963968. Its totient is φ = 288827324.

The previous prime is 866481971. The next prime is 866481997. The reversal of 866481978 is 879184668.

It is a sphenic number, since it is the product of 3 distinct primes.

866481978 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (866481971) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72206826 + ... + 72206837.

It is an arithmetic number, because the mean of its divisors is an integer number (216620496).

Almost surely, 2^866481978 is an apocalyptic number.

866481978 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

866481978 is a wasteful number, since it uses less digits than its factorization.

866481978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144413668.

The product of its digits is 4644864, while the sum is 57.

The square root of 866481978 is about 29436.0659395919. The cubic root of 866481978 is about 953.3517718843.

The spelling of 866481978 in words is "eight hundred sixty-six million, four hundred eighty-one thousand, nine hundred seventy-eight".