856424449 has 4 divisors (see below), whose sum is σ = 901499440. Its totient is φ = 811349460.

The previous prime is 856424447. The next prime is 856424501. The reversal of 856424449 is 944424658.

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.

It is a cyclic number.

It is not a de Polignac number, because 856424449 - 2¹ = 856424447 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 856424399 and 856424408.

It is not an unprimeable number, because it can be changed into a prime (856424447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22537467 + ... + 22537504.

It is an arithmetic number, because the mean of its divisors is an integer number (225374860).

It is a Proth number, since it is equal to 3267 ⋅ 2¹⁸ + 1 and 3267 < 2¹⁸.

Almost surely, 2^856424449 is an apocalyptic number.

It is an amenable number.

856424449 is a deficient number, since it is larger than the sum of its proper divisors (45074991).

856424449 is a wasteful number, since it uses less digits than its factorization.

856424449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45074990.

The product of its digits is 1105920, while the sum is 46.

The square root of 856424449 is about 29264.7304617692. The cubic root of 856424449 is about 949.6487894734.

The spelling of 856424449 in words is "eight hundred fifty-six million, four hundred twenty-four thousand, four hundred forty-nine".