891749 has 2 divisors, whose sum is σ = 891750. Its totient is φ = 891748.

The previous prime is 891743. The next prime is 891763. The reversal of 891749 is 947198.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 889249 + 2500 = 943^2 + 50^2 .

It is a cyclic number.

It is not a de Polignac number, because 891749 - 2⁸ = 891493 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (891743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 445874 + 445875.

It is an arithmetic number, because the mean of its divisors is an integer number (445875).

2⁸⁹¹⁷⁴⁹ is an apocalyptic number.

It is an amenable number.

891749 is a deficient number, since it is larger than the sum of its proper divisors (1).

891749 is an equidigital number, since it uses as much as digits as its factorization.

891749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 38.

The square root of 891749 is about 944.3246263865. The cubic root of 891749 is about 96.2529857959.

The spelling of 891749 in words is "eight hundred ninety-one thousand, seven hundred forty-nine".