856745137 has 2 divisors, whose sum is σ = 856745138. Its totient is φ = 856745136.

The previous prime is 856745129. The next prime is 856745161. The reversal of 856745137 is 731547658.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 823058721 + 33686416 = 28689^2 + 5804^2 .

It is a cyclic number.

It is not a de Polignac number, because 856745137 - 2³ = 856745129 is a prime.

It is not a weakly prime, because it can be changed into another prime (856745117) 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 as a sum of consecutive naturals, namely, 428372568 + 428372569.

It is an arithmetic number, because the mean of its divisors is an integer number (428372569).

Almost surely, 2^856745137 is an apocalyptic number.

It is an amenable number.

856745137 is a deficient number, since it is larger than the sum of its proper divisors (1).

856745137 is an equidigital number, since it uses as much as digits as its factorization.

856745137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 705600, while the sum is 46.

The square root of 856745137 is about 29270.2090358098. The cubic root of 856745137 is about 949.7673066282.

The spelling of 856745137 in words is "eight hundred fifty-six million, seven hundred forty-five thousand, one hundred thirty-seven".