81224960 has 144 divisors (see below), whose sum is σ = 211921920. Its totient is φ = 29736960.

The previous prime is 81224921. The next prime is 81224993. The reversal of 81224960 is 6942218.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 912596 + ... + 912684.

It is an arithmetic number, because the mean of its divisors is an integer number (1471680).

Almost surely, 2^81224960 is an apocalyptic number.

81224960 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 81224960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105960960).

81224960 is an abundant number, since it is smaller than the sum of its proper divisors (130696960).

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

81224960 is a wasteful number, since it uses less digits than its factorization.

81224960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 81224960 is about 9012.4891123374. The cubic root of 81224960 is about 433.0750545047.

The spelling of 81224960 in words is "eighty-one million, two hundred twenty-four thousand, nine hundred sixty".