81061344 has 192 divisors, whose sum is σ = 291271680. Its totient is φ = 21358080.

The previous prime is 81061313. The next prime is 81061397. The reversal of 81061344 is 44316018.

81061344 is a `hidden beast` number, since 8 + 1 + 0 + 613 + 44 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 78109 + ... + 79139.

It is an arithmetic number, because the mean of its divisors is an integer number (1517040).

Almost surely, 2^81061344 is an apocalyptic number.

81061344 is a gapful number since it is divisible by the number (84) 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 81061344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145635840).

81061344 is an abundant number, since it is smaller than the sum of its proper divisors (210210336).

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

81061344 is a wasteful number, since it uses less digits than its factorization.

81061344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1070 (or 1056 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 81061344 is about 9003.4073549962. The cubic root of 81061344 is about 432.7840698977.

The spelling of 81061344 in words is "eighty-one million, sixty-one thousand, three hundred forty-four".