866320780 has 48 divisors (see below), whose sum is σ = 1991372544. Its totient is φ = 314622720.

The previous prime is 866320769. The next prime is 866320811. The reversal of 866320780 is 87023668.

It is a happy number.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11452 + ... + 43171.

It is an arithmetic number, because the mean of its divisors is an integer number (41486928).

Almost surely, 2^866320780 is an apocalyptic number.

It is an amenable number.

866320780 is an abundant number, since it is smaller than the sum of its proper divisors (1125051764).

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

866320780 is a wasteful number, since it uses less digits than its factorization.

866320780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54706 (or 54704 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 40.

The square root of 866320780 is about 29433.3277085687. The cubic root of 866320780 is about 953.2926485428.

The spelling of 866320780 in words is "eight hundred sixty-six million, three hundred twenty thousand, seven hundred eighty".