866016640 has 64 divisors (see below), whose sum is σ = 2074533120. Its totient is φ = 345702400.

The previous prime is 866016629. The next prime is 866016649. The reversal of 866016640 is 46610668.

866016640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (64).

It is a self number, because there is not a number n which added to its sum of digits gives 866016640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866016649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 409185 + ... + 411295.

It is an arithmetic number, because the mean of its divisors is an integer number (32414580).

Almost surely, 2^866016640 is an apocalyptic number.

866016640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 866016640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1037266560).

866016640 is an abundant number, since it is smaller than the sum of its proper divisors (1208516480).

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

866016640 is a wasteful number, since it uses less digits than its factorization.

866016640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2771 (or 2759 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 37.

The square root of 866016640 is about 29428.1606628753. The cubic root of 866016640 is about 953.1810777218.

The spelling of 866016640 in words is "eight hundred sixty-six million, sixteen thousand, six hundred forty".