81141544 has 64 divisors (see below), whose sum is σ = 178381440. Its totient is φ = 34191360.

The previous prime is 81141509. The next prime is 81141581. The reversal of 81141544 is 44514118.

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 15 ways as a sum of consecutive naturals, for example, 108837 + ... + 109579.

It is an arithmetic number, because the mean of its divisors is an integer number (2787210).

Almost surely, 2^81141544 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81141544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89190720).

81141544 is an abundant number, since it is smaller than the sum of its proper divisors (97239896).

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

81141544 is a wasteful number, since it uses less digits than its factorization.

81141544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 850 (or 846 counting only the distinct ones).

The product of its digits is 2560, while the sum is 28.

The square root of 81141544 is about 9007.8601232479. The cubic root of 81141544 is about 432.9267513130.

The spelling of 81141544 in words is "eighty-one million, one hundred forty-one thousand, five hundred forty-four".