891618 has 64 divisors (see below), whose sum is σ = 2322432. Its totient is φ = 221760.

The previous prime is 891617. The next prime is 891629. The reversal of 891618 is 816198.

891618 = T₉₂ + T₉₃ + ... + T₁₈₂.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (891617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12523 + ... + 12593.

It is an arithmetic number, because the mean of its divisors is an integer number (36288).

2⁸⁹¹⁶¹⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 891618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1161216).

891618 is an abundant number, since it is smaller than the sum of its proper divisors (1430814).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

891618 is a wasteful number, since it uses less digits than its factorization.

891618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119.

The product of its digits is 3456, while the sum is 33.

The square root of 891618 is about 944.2552620981. The cubic root of 891618 is about 96.2482723027.

The spelling of 891618 in words is "eight hundred ninety-one thousand, six hundred eighteen".