856249389 has 12 divisors (see below), whose sum is σ = 1279453500. Its totient is φ = 551148864.

The previous prime is 856249379. The next prime is 856249399. The reversal of 856249389 is 983942658.

856249389 is a `hidden beast` number, since 8 + 5 + 624 + 9 + 3 + 8 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (856249379) and next prime (856249399).

It can be written as a sum of positive squares in 2 ways, for example, as 562401225 + 293848164 = 23715^2 + 17142^2 .

It is not a de Polignac number, because 856249389 - 2¹¹ = 856247341 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856249349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1640064 + ... + 1640585.

It is an arithmetic number, because the mean of its divisors is an integer number (106621125).

Almost surely, 2^856249389 is an apocalyptic number.

It is an amenable number.

856249389 is a deficient number, since it is larger than the sum of its proper divisors (423204111).

856249389 is a wasteful number, since it uses less digits than its factorization.

856249389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3280684 (or 3280681 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 54.

The square root of 856249389 is about 29261.7393365466. The cubic root of 856249389 is about 949.5840797974.

The spelling of 856249389 in words is "eight hundred fifty-six million, two hundred forty-nine thousand, three hundred eighty-nine".