856535680 has 384 divisors, whose sum is σ = 2813045760. Its totient is φ = 245145600.

The previous prime is 856535671. The next prime is 856535689. The reversal of 856535680 is 86535658.

It is an interprime number because it is at equal distance from previous prime (856535671) and next prime (856535689).

It is a super-2 number, since 2×856535680² = 1467306742226124800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 856535680.

It is not an unprimeable number, because it can be changed into a prime (856535689) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4484385 + ... + 4484575.

It is an arithmetic number, because the mean of its divisors is an integer number (7325640).

Almost surely, 2^856535680 is an apocalyptic number.

856535680 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 856535680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1406522880).

856535680 is an abundant number, since it is smaller than the sum of its proper divisors (1956510080).

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

856535680 is a wasteful number, since it uses less digits than its factorization.

856535680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248 (or 229 counting only the distinct ones).

The product of its (nonzero) digits is 864000, while the sum is 46.

The square root of 856535680 is about 29266.6308276166. The cubic root of 856535680 is about 949.6899006350.

The spelling of 856535680 in words is "eight hundred fifty-six million, five hundred thirty-five thousand, six hundred eighty".