891647 has 2 divisors, whose sum is σ = 891648. Its totient is φ = 891646.

The previous prime is 891643. The next prime is 891659. The reversal of 891647 is 746198.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 891647 - 2² = 891643 is a prime.

It is a plaindrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (891643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 445823 + 445824.

It is an arithmetic number, because the mean of its divisors is an integer number (445824).

2⁸⁹¹⁶⁴⁷ is an apocalyptic number.

891647 is a deficient number, since it is larger than the sum of its proper divisors (1).

891647 is an equidigital number, since it uses as much as digits as its factorization.

891647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 35.

The square root of 891647 is about 944.2706179904. The cubic root of 891647 is about 96.2493157876.

The spelling of 891647 in words is "eight hundred ninety-one thousand, six hundred forty-seven".