857118641 has 2 divisors, whose sum is σ = 857118642. Its totient is φ = 857118640.

The previous prime is 857118629. The next prime is 857118643. The reversal of 857118641 is 146811758.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 437688241 + 419430400 = 20921^2 + 20480^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857118641 is a prime.

Together with 857118643, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (857118643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428559320 + 428559321.

It is an arithmetic number, because the mean of its divisors is an integer number (428559321).

Almost surely, 2^857118641 is an apocalyptic number.

It is an amenable number.

857118641 is a deficient number, since it is larger than the sum of its proper divisors (1).

857118641 is an equidigital number, since it uses as much as digits as its factorization.

857118641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 41.

The square root of 857118641 is about 29276.5886161622. The cubic root of 857118641 is about 949.9053057968.

The spelling of 857118641 in words is "eight hundred fifty-seven million, one hundred eighteen thousand, six hundred forty-one".