81753319536 has 320 divisors, whose sum is σ = 260726169600. Its totient is φ = 21572812800.

The previous prime is 81753319513. The next prime is 81753319537. The reversal of 81753319536 is 63591335718.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81753319537) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 26882176 + ... + 26885216.

It is an arithmetic number, because the mean of its divisors is an integer number (814769280).

Almost surely, 2^81753319536 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 81753319536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130363084800).

81753319536 is an abundant number, since it is smaller than the sum of its proper divisors (178972850064).

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

81753319536 is a wasteful number, since it uses less digits than its factorization.

81753319536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3208 (or 3202 counting only the distinct ones).

The product of its digits is 2041200, while the sum is 51.

The spelling of 81753319536 in words is "eighty-one billion, seven hundred fifty-three million, three hundred nineteen thousand, five hundred thirty-six".