81346560 has 120 divisors (see below), whose sum is σ = 261087456. Its totient is φ = 21626880.

The previous prime is 81346549. The next prime is 81346579. The reversal of 81346560 is 6564318.

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 245595 + ... + 245925.

Almost surely, 2^81346560 is an apocalyptic number.

81346560 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 81346560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130543728).

81346560 is an abundant number, since it is smaller than the sum of its proper divisors (179740896).

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

81346560 is an equidigital number, since it uses as much as digits as its factorization.

81346560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 367 (or 341 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 81346560 is about 9019.2327833358. The cubic root of 81346560 is about 433.2910622803.

The spelling of 81346560 in words is "eighty-one million, three hundred forty-six thousand, five hundred sixty".