81963744 has 96 divisors (see below), whose sum is σ = 226800000. Its totient is φ = 25880064.

The previous prime is 81963727. The next prime is 81963751. The reversal of 81963744 is 44736918.

It is a tau number, because it is divible by the number of its divisors (96).

It is a junction number, because it is equal to n+sod(n) for n = 81963696 and 81963705.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 164007 + ... + 164505.

It is an arithmetic number, because the mean of its divisors is an integer number (2362500).

Almost surely, 2^81963744 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81963744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113400000).

81963744 is an abundant number, since it is smaller than the sum of its proper divisors (144836256).

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

81963744 is a wasteful number, since it uses less digits than its factorization.

81963744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 600 (or 592 counting only the distinct ones).

The product of its digits is 145152, while the sum is 42.

The square root of 81963744 is about 9053.3830141003. The cubic root of 81963744 is about 434.3841092512.

The spelling of 81963744 in words is "eighty-one million, nine hundred sixty-three thousand, seven hundred forty-four".