856506307786 has 4 divisors (see below), whose sum is σ = 1284759461682. Its totient is φ = 428253153892.

The previous prime is 856506307757. The next prime is 856506307799. The reversal of 856506307786 is 687703605658.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 825225079561 + 31281228225 = 908419^2 + 176865^2 .

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 as a sum of consecutive naturals, namely, 214126576945 + ... + 214126576948.

Almost surely, 2^856506307786 is an apocalyptic number.

856506307786 is a deficient number, since it is larger than the sum of its proper divisors (428253153896).

856506307786 is a wasteful number, since it uses less digits than its factorization.

856506307786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428253153895.

The product of its (nonzero) digits is 50803200, while the sum is 61.

The spelling of 856506307786 in words is "eight hundred fifty-six billion, five hundred six million, three hundred seven thousand, seven hundred eighty-six".