856805280040 has 64 divisors (see below), whose sum is σ = 2020263897600. Its totient is φ = 326414111232.

The previous prime is 856805279987. The next prime is 856805280077. The reversal of 856805280040 is 40082508658.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 1784160 + ... + 2212879.

It is an arithmetic number, because the mean of its divisors is an integer number (31566623400).

Almost surely, 2^856805280040 is an apocalyptic number.

It is an amenable number.

856805280040 is an abundant number, since it is smaller than the sum of its proper divisors (1163458617560).

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

856805280040 is a wasteful number, since it uses less digits than its factorization.

856805280040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3997306 (or 3997302 counting only the distinct ones).

The product of its (nonzero) digits is 614400, while the sum is 46.

Adding to 856805280040 its reverse (40082508658), we get a palindrome (896887788698).

The spelling of 856805280040 in words is "eight hundred fifty-six billion, eight hundred five million, two hundred eighty thousand, forty".