856509400 has 48 divisors (see below), whose sum is σ = 1995954840. Its totient is φ = 341817600.

The previous prime is 856509383. The next prime is 856509439. The reversal of 856509400 is 4905658.

856509400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 856509400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 86715 + ... + 96085.

Almost surely, 2^856509400 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 856509400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (997977420).

856509400 is an abundant number, since it is smaller than the sum of its proper divisors (1139445440).

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

856509400 is a wasteful number, since it uses less digits than its factorization.

856509400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9844 (or 9835 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 37.

The square root of 856509400 is about 29266.1818486799. The cubic root of 856509400 is about 949.6801878246.

The spelling of 856509400 in words is "eight hundred fifty-six million, five hundred nine thousand, four hundred".