981618 has 32 divisors (see below), whose sum is σ = 2177280. Its totient is φ = 292560.

The previous prime is 981601. The next prime is 981623. The reversal of 981618 is 816189.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 6993 + ... + 7131.

It is an arithmetic number, because the mean of its divisors is an integer number (68040).

2⁹⁸¹⁶¹⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 981618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1088640).

981618 is an abundant number, since it is smaller than the sum of its proper divisors (1195662).

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

981618 is a wasteful number, since it uses less digits than its factorization.

981618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262.

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

The square root of 981618 is about 990.7663700389. The cubic root of 981618 is about 99.3834734280.

The spelling of 981618 in words is "nine hundred eighty-one thousand, six hundred eighteen".