851381746560 has 640 divisors, whose sum is σ = 3100942310400. Its totient is φ = 222563303424.

The previous prime is 851381746559. The next prime is 851381746561. The reversal of 851381746560 is 65647183158.

It is a happy number.

851381746560 is a `hidden beast` number, since 8 + 5 + 1 + 3 + 8 + 1 + 74 + 6 + 560 = 666.

It is an interprime number because it is at equal distance from previous prime (851381746559) and next prime (851381746561).

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 851381746497 and 851381746506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (851381746561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 585946794 + ... + 585948246.

It is an arithmetic number, because the mean of its divisors is an integer number (4845222360).

Almost surely, 2^851381746560 is an apocalyptic number.

851381746560 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 851381746560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1550471155200).

851381746560 is an abundant number, since it is smaller than the sum of its proper divisors (2249560563840).

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

851381746560 is a wasteful number, since it uses less digits than its factorization.

851381746560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1700 (or 1679 counting only the distinct ones).

The product of its (nonzero) digits is 4838400, while the sum is 54.

The spelling of 851381746560 in words is "eight hundred fifty-one billion, three hundred eighty-one million, seven hundred forty-six thousand, five hundred sixty".