856633439 has 4 divisors (see below), whose sum is σ = 859794720. Its totient is φ = 853472160.

The previous prime is 856633423. The next prime is 856633471. The reversal of 856633439 is 934336658.

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

It is a cyclic number.

It is not a de Polignac number, because 856633439 - 2⁴ = 856633423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 856633393 and 856633402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856633489) 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, 1580234 + ... + 1580775.

It is an arithmetic number, because the mean of its divisors is an integer number (214948680).

Almost surely, 2^856633439 is an apocalyptic number.

856633439 is a deficient number, since it is larger than the sum of its proper divisors (3161281).

856633439 is a wasteful number, since it uses less digits than its factorization.

856633439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3161280.

The product of its digits is 1399680, while the sum is 47.

The square root of 856633439 is about 29268.3009243789. The cubic root of 856633439 is about 949.7260295845.

The spelling of 856633439 in words is "eight hundred fifty-six million, six hundred thirty-three thousand, four hundred thirty-nine".