856728223 has 4 divisors (see below), whose sum is σ = 922630408. Its totient is φ = 790826040.

The previous prime is 856728193. The next prime is 856728239. The reversal of 856728223 is 322827658.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 322827658 = 2 ⋅161413829.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-856728223 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 856728223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856728283) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32951073 + ... + 32951098.

It is an arithmetic number, because the mean of its divisors is an integer number (230657602).

Almost surely, 2^856728223 is an apocalyptic number.

856728223 is a deficient number, since it is larger than the sum of its proper divisors (65902185).

856728223 is a wasteful number, since it uses less digits than its factorization.

856728223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65902184.

The product of its digits is 322560, while the sum is 43.

The square root of 856728223 is about 29269.9201058015. The cubic root of 856728223 is about 949.7610564342.

The spelling of 856728223 in words is "eight hundred fifty-six million, seven hundred twenty-eight thousand, two hundred twenty-three".