856865753 has 4 divisors (see below), whose sum is σ = 860640720. Its totient is φ = 853090788.

The previous prime is 856865749. The next prime is 856865783. The reversal of 856865753 is 357568658.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 357568658 = 2 ⋅178784329.

It is a cyclic number.

It is not a de Polignac number, because 856865753 - 2² = 856865749 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 856865695 and 856865704.

It is not an unprimeable number, because it can be changed into a prime (856865783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1887143 + ... + 1887596.

It is an arithmetic number, because the mean of its divisors is an integer number (215160180).

Almost surely, 2^856865753 is an apocalyptic number.

It is an amenable number.

856865753 is a deficient number, since it is larger than the sum of its proper divisors (3774967).

856865753 is a wasteful number, since it uses less digits than its factorization.

856865753 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3774966.

The product of its digits is 6048000, while the sum is 53.

The square root of 856865753 is about 29272.2693517260. The cubic root of 856865753 is about 949.8118752142.

The spelling of 856865753 in words is "eight hundred fifty-six million, eight hundred sixty-five thousand, seven hundred fifty-three".