91644 has 24 divisors (see below), whose sum is σ = 244608. Its totient is φ = 26160.

The previous prime is 91639. The next prime is 91673. The reversal of 91644 is 44619.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 462 + ... + 629.

It is an arithmetic number, because the mean of its divisors is an integer number (10192).

2⁹¹⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

91644 is an abundant number, since it is smaller than the sum of its proper divisors (152964).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122304).

91644 is a wasteful number, since it uses less digits than its factorization.

91644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1105 (or 1103 counting only the distinct ones).

The product of its digits is 864, while the sum is 24.

The square root of 91644 is about 302.7276003274. The cubic root of 91644 is about 45.0852704179.

It can be divided in two parts, 916 and 44, that multiplied together give a palindrome (40304).

The spelling of 91644 in words is "ninety-one thousand, six hundred forty-four".