81107532240 has 480 divisors, whose sum is σ = 302284224000. Its totient is φ = 17926530048.

The previous prime is 81107532227. The next prime is 81107532269. The reversal of 81107532240 is 4223570118.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 54107011 + ... + 54108509.

It is an arithmetic number, because the mean of its divisors is an integer number (629758800).

Almost surely, 2^81107532240 is an apocalyptic number.

81107532240 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 81107532240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151142112000).

81107532240 is an abundant number, since it is smaller than the sum of its proper divisors (221176691760).

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

81107532240 is a wasteful number, since it uses less digits than its factorization.

81107532240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1679 (or 1666 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 33.

The spelling of 81107532240 in words is "eighty-one billion, one hundred seven million, five hundred thirty-two thousand, two hundred forty".