891247 has 4 divisors (see below), whose sum is σ = 1018576. Its totient is φ = 763920.

The previous prime is 891239. The next prime is 891251. The reversal of 891247 is 742198.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 742198 = 2 ⋅371099.

It is a cyclic number.

It is not a de Polignac number, because 891247 - 2³ = 891239 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (891277) 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 in 3 ways as a sum of consecutive naturals, for example, 63654 + ... + 63667.

It is an arithmetic number, because the mean of its divisors is an integer number (254644).

2⁸⁹¹²⁴⁷ is an apocalyptic number.

891247 is a deficient number, since it is larger than the sum of its proper divisors (127329).

891247 is a wasteful number, since it uses less digits than its factorization.

891247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127328.

The product of its digits is 4032, while the sum is 31.

The square root of 891247 is about 944.0587905422. The cubic root of 891247 is about 96.2349208963.

The spelling of 891247 in words is "eight hundred ninety-one thousand, two hundred forty-seven".