857749 has 2 divisors, whose sum is σ = 857750. Its totient is φ = 857748.

The previous prime is 857743. The next prime is 857809. The reversal of 857749 is 947758.

857749 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 515524 + 342225 = 718^2 + 585^2 .

It is a cyclic number.

It is not a de Polignac number, because 857749 - 2³ = 857741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (857741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428874 + 428875.

It is an arithmetic number, because the mean of its divisors is an integer number (428875).

2⁸⁵⁷⁷⁴⁹ is an apocalyptic number.

It is an amenable number.

857749 is a deficient number, since it is larger than the sum of its proper divisors (1).

857749 is an equidigital number, since it uses as much as digits as its factorization.

857749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 70560, while the sum is 40.

The square root of 857749 is about 926.1473964764. The cubic root of 857749 is about 95.0138114730.

Subtracting 857749 from its reverse (947758), we obtain a palindrome (90009).

The spelling of 857749 in words is "eight hundred fifty-seven thousand, seven hundred forty-nine".