81768960 has 480 divisors, whose sum is σ = 359441280. Its totient is φ = 17252352.

The previous prime is 81768959. The next prime is 81768961. The reversal of 81768960 is 6986718.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (81768959) and next prime (81768961).

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81768961) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6289914 + ... + 6289926.

It is an arithmetic number, because the mean of its divisors is an integer number (748836).

Almost surely, 2^81768960 is an apocalyptic number.

81768960 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81768960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179720640).

81768960 is an abundant number, since it is smaller than the sum of its proper divisors (277672320).

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

81768960 is a wasteful number, since it uses less digits than its factorization.

81768960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 81768960 is about 9042.6190896222. The cubic root of 81768960 is about 434.0397367115.

It can be divided in two parts, 81768 and 960, that added together give a palindrome (82728).

The spelling of 81768960 in words is "eighty-one million, seven hundred sixty-eight thousand, nine hundred sixty".