81368 has 16 divisors (see below), whose sum is σ = 174480. Its totient is φ = 34848.

The previous prime is 81359. The next prime is 81371. The reversal of 81368 is 86318.

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 671 + ... + 782.

It is an arithmetic number, because the mean of its divisors is an integer number (10905).

2⁸¹³⁶⁸ is an apocalyptic number.

It is an amenable number.

81368 is an abundant number, since it is smaller than the sum of its proper divisors (93112).

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 (87240).

81368 is a wasteful number, since it uses less digits than its factorization.

81368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1466 (or 1462 counting only the distinct ones).

The product of its digits is 1152, while the sum is 26.

The square root of 81368 is about 285.2507668701. The cubic root of 81368 is about 43.3329125534.

Subtracting 81368 from its reverse (86318), we obtain a triangular number (4950 = T₉₉).

The spelling of 81368 in words is "eighty-one thousand, three hundred sixty-eight".