856851907464 has 256 divisors, whose sum is σ = 2749357209600. Its totient is φ = 242193888000.

The previous prime is 856851907463. The next prime is 856851907487. The reversal of 856851907464 is 464709158658.

856851907464 is a `hidden beast` number, since 8 + 5 + 6 + 85 + 1 + 90 + 7 + 464 = 666.

It is a super-2 number, since 2×856851907464² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (856851907463) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 132821439 + ... + 132827889.

It is an arithmetic number, because the mean of its divisors is an integer number (10739676600).

Almost surely, 2^856851907464 is an apocalyptic number.

856851907464 is a gapful number since it is divisible by the number (84) 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 856851907464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1374678604800).

856851907464 is an abundant number, since it is smaller than the sum of its proper divisors (1892505302136).

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

856851907464 is a wasteful number, since it uses less digits than its factorization.

856851907464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7401 (or 7391 counting only the distinct ones).

The product of its (nonzero) digits is 58060800, while the sum is 63.

The spelling of 856851907464 in words is "eight hundred fifty-six billion, eight hundred fifty-one million, nine hundred seven thousand, four hundred sixty-four".