81960 has 32 divisors (see below), whose sum is σ = 246240. Its totient is φ = 21824.

The previous prime is 81953. The next prime is 81967. The reversal of 81960 is 6918.

81960 = T₁₂₃ + T₁₂₄ + ... + T₁₃₂.

It is an interprime number because it is at equal distance from previous prime (81953) and next prime (81967).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 81960.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 81960.

It is not an unprimeable number, because it can be changed into a prime (81967) by changing a digit.

81960 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 222 + ... + 461.

It is an arithmetic number, because the mean of its divisors is an integer number (7695).

2⁸¹⁹⁶⁰ is an apocalyptic number.

It is an amenable number.

81960 is an abundant number, since it is smaller than the sum of its proper divisors (164280).

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 (123120).

81960 is a wasteful number, since it uses less digits than its factorization.

81960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 697 (or 693 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 81960 is about 286.2865697164. The cubic root of 81960 is about 43.4377495112.

The spelling of 81960 in words is "eighty-one thousand, nine hundred sixty".