856001660 has 48 divisors (see below), whose sum is σ = 1850887584. Its totient is φ = 332299008.

The previous prime is 856001651. The next prime is 856001669. The reversal of 856001660 is 66100658.

It is an interprime number because it is at equal distance from previous prime (856001651) and next prime (856001669).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856001669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 344342 + ... + 346818.

It is an arithmetic number, because the mean of its divisors is an integer number (38560158).

Almost surely, 2^856001660 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 856001660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (925443792).

856001660 is an abundant number, since it is smaller than the sum of its proper divisors (994885924).

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

856001660 is a wasteful number, since it uses less digits than its factorization.

856001660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2990 (or 2988 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 856001660 is about 29257.5060454578. The cubic root of 856001660 is about 949.4924934724.

The spelling of 856001660 in words is "eight hundred fifty-six million, one thousand, six hundred sixty".