856787280 has 40 divisors (see below), whose sum is σ = 2656041312. Its totient is φ = 228476544.

The previous prime is 856787279. The next prime is 856787287. The reversal of 856787280 is 82787658.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856787287) 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 7 ways as a sum of consecutive naturals, for example, 1784734 + ... + 1785213.

Almost surely, 2^856787280 is an apocalyptic number.

856787280 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

856787280 is an abundant number, since it is smaller than the sum of its proper divisors (1799254032).

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

856787280 is a wasteful number, since it uses less digits than its factorization.

856787280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3569963 (or 3569957 counting only the distinct ones).

The product of its (nonzero) digits is 1505280, while the sum is 51.

The square root of 856787280 is about 29270.9289227383. The cubic root of 856787280 is about 949.7828792824.

The spelling of 856787280 in words is "eight hundred fifty-six million, seven hundred eighty-seven thousand, two hundred eighty".