81540151800 has 384 divisors, whose sum is σ = 265232309760. Its totient is φ = 20705126400.

The previous prime is 81540151733. The next prime is 81540151807. The reversal of 81540151800 is 815104518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81540151807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 310038469 + ... + 310038731.

It is an arithmetic number, because the mean of its divisors is an integer number (690709140).

Almost surely, 2^81540151800 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 81540151800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132616154880).

81540151800 is an abundant number, since it is smaller than the sum of its proper divisors (183692157960).

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

81540151800 is a wasteful number, since it uses less digits than its factorization.

81540151800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 583 (or 574 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 33.

The spelling of 81540151800 in words is "eighty-one billion, five hundred forty million, one hundred fifty-one thousand, eight hundred".