857001564640 has 96 divisors (see below), whose sum is σ = 2188115881056. Its totient is φ = 315312998400.

The previous prime is 857001564611. The next prime is 857001564641. The reversal of 857001564640 is 46465100758.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (857001564641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139311 + ... + 1316590.

It is an arithmetic number, because the mean of its divisors is an integer number (22792873761).

Almost surely, 2^857001564640 is an apocalyptic number.

857001564640 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 857001564640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1094057940528).

857001564640 is an abundant number, since it is smaller than the sum of its proper divisors (1331114316416).

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

857001564640 is a wasteful number, since it uses less digits than its factorization.

857001564640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1456212 (or 1456204 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 46.

The spelling of 857001564640 in words is "eight hundred fifty-seven billion, one million, five hundred sixty-four thousand, six hundred forty".