856724804965 has 4 divisors (see below), whose sum is σ = 1028069765964. Its totient is φ = 685379843968.

The previous prime is 856724804951. The next prime is 856724804993. The reversal of 856724804965 is 569408427658.

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

It can be written as a sum of positive squares in 2 ways, for example, as 504166742209 + 352558062756 = 710047^2 + 593766^2 .

It is a cyclic number.

It is not a de Polignac number, because 856724804965 - 2¹⁹ = 856724280677 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 856724804897 and 856724804906.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85672480492 + ... + 85672480501.

It is an arithmetic number, because the mean of its divisors is an integer number (257017441491).

Almost surely, 2^856724804965 is an apocalyptic number.

It is an amenable number.

856724804965 is a deficient number, since it is larger than the sum of its proper divisors (171344960999).

856724804965 is a wasteful number, since it uses less digits than its factorization.

856724804965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171344960998.

The product of its (nonzero) digits is 116121600, while the sum is 64.

The spelling of 856724804965 in words is "eight hundred fifty-six billion, seven hundred twenty-four million, eight hundred four thousand, nine hundred sixty-five".