856684705 has 4 divisors (see below), whose sum is σ = 1028021652. Its totient is φ = 685347760.

The previous prime is 856684669. The next prime is 856684729. The reversal of 856684705 is 507486658.

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 666878976 + 189805729 = 25824^2 + 13777^2 .

It is not a de Polignac number, because 856684705 - 2⁹ = 856684193 is a prime.

It is a Duffinian 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, 85668466 + ... + 85668475.

It is an arithmetic number, because the mean of its divisors is an integer number (257005413).

Almost surely, 2^856684705 is an apocalyptic number.

It is an amenable number.

856684705 is a deficient number, since it is larger than the sum of its proper divisors (171336947).

856684705 is a wasteful number, since it uses less digits than its factorization.

856684705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171336946.

The product of its (nonzero) digits is 1612800, while the sum is 49.

The square root of 856684705 is about 29269.1767051962. The cubic root of 856684705 is about 949.7449749433.

The spelling of 856684705 in words is "eight hundred fifty-six million, six hundred eighty-four thousand, seven hundred five".