856250640 has 120 divisors (see below), whose sum is σ = 3286390848. Its totient is φ = 195713280.

The previous prime is 856250627. The next prime is 856250641. The reversal of 856250640 is 46052658.

856250640 is a `hidden beast` number, since 8 + 5 + 6 + 2 + 5 + 0 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 856250595 and 856250604.

It is not an unprimeable number, because it can be changed into a prime (856250641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 79906 + ... + 89985.

Almost surely, 2^856250640 is an apocalyptic number.

856250640 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

856250640 is an abundant number, since it is smaller than the sum of its proper divisors (2430140208).

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

856250640 is a wasteful number, since it uses less digits than its factorization.

856250640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169917 (or 169908 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The square root of 856250640 is about 29261.7607125750. The cubic root of 856250640 is about 949.5845422519.

The spelling of 856250640 in words is "eight hundred fifty-six million, two hundred fifty thousand, six hundred forty".