81546040 has 64 divisors (see below), whose sum is σ = 193052160. Its totient is φ = 30940800.

The previous prime is 81546029. The next prime is 81546067. The reversal of 81546040 is 4064518.

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 15 ways as a sum of consecutive naturals, for example, 138627 + ... + 139213.

It is an arithmetic number, because the mean of its divisors is an integer number (3016440).

Almost surely, 2^81546040 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 81546040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96526080).

81546040 is an abundant number, since it is smaller than the sum of its proper divisors (111506120).

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

81546040 is a wasteful number, since it uses less digits than its factorization.

81546040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 772 (or 768 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 81546040 is about 9030.2846023810. The cubic root of 81546040 is about 433.6449487723.

It can be divided in two parts, 81 and 546040, that added together give a square (546121 = 739²).

The spelling of 81546040 in words is "eighty-one million, five hundred forty-six thousand, forty".