856703657 has 2 divisors, whose sum is σ = 856703658. Its totient is φ = 856703656.

The previous prime is 856703621. The next prime is 856703669. The reversal of 856703657 is 756307658.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 785064361 + 71639296 = 28019^2 + 8464^2 .

It is a cyclic number.

It is not a de Polignac number, because 856703657 - 2¹⁰ = 856702633 is a prime.

It is not a weakly prime, because it can be changed into another prime (856703857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428351828 + 428351829.

It is an arithmetic number, because the mean of its divisors is an integer number (428351829).

Almost surely, 2^856703657 is an apocalyptic number.

It is an amenable number.

856703657 is a deficient number, since it is larger than the sum of its proper divisors (1).

856703657 is an equidigital number, since it uses as much as digits as its factorization.

856703657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1058400, while the sum is 47.

The square root of 856703657 is about 29269.5004569603. The cubic root of 856703657 is about 949.7519784666.

The spelling of 856703657 in words is "eight hundred fifty-six million, seven hundred three thousand, six hundred fifty-seven".