856587512640 has 224 divisors, whose sum is σ = 2771851590144. Its totient is φ = 224060866560.

The previous prime is 856587512593. The next prime is 856587512689. The reversal of 856587512640 is 46215785658.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21471592 + ... + 21511448.

It is an arithmetic number, because the mean of its divisors is an integer number (12374337456).

Almost surely, 2^856587512640 is an apocalyptic number.

856587512640 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 856587512640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1385925795072).

856587512640 is an abundant number, since it is smaller than the sum of its proper divisors (1915264077504).

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

856587512640 is a wasteful number, since it uses less digits than its factorization.

856587512640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40305 (or 40295 counting only the distinct ones).

The product of its (nonzero) digits is 16128000, while the sum is 57.

The spelling of 856587512640 in words is "eight hundred fifty-six billion, five hundred eighty-seven million, five hundred twelve thousand, six hundred forty".