856659240 has 320 divisors, whose sum is σ = 3098684160. Its totient is φ = 211507200.

The previous prime is 856659191. The next prime is 856659241. The reversal of 856659240 is 42956658.

856659240 is a `hidden beast` number, since 8 + 56 + 6 + 592 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856659241) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 5673165 + ... + 5673315.

It is an arithmetic number, because the mean of its divisors is an integer number (9683388).

Almost surely, 2^856659240 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 856659240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1549342080).

856659240 is an abundant number, since it is smaller than the sum of its proper divisors (2242024920).

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

856659240 is a wasteful number, since it uses less digits than its factorization.

856659240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294 (or 281 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The square root of 856659240 is about 29268.7416880193. The cubic root of 856659240 is about 949.7355644428.

The spelling of 856659240 in words is "eight hundred fifty-six million, six hundred fifty-nine thousand, two hundred forty".