81555341532 has 48 divisors (see below), whose sum is σ = 221046185472. Its totient is φ = 22919532480.

The previous prime is 81555341531. The next prime is 81555341573. The reversal of 81555341532 is 23514355518.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81555341531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7953048 + ... + 7963295.

It is an arithmetic number, because the mean of its divisors is an integer number (4605128864).

Almost surely, 2^81555341532 is an apocalyptic number.

It is an amenable number.

81555341532 is an abundant number, since it is smaller than the sum of its proper divisors (139490843940).

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

81555341532 is a wasteful number, since it uses less digits than its factorization.

81555341532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15916418 (or 15916416 counting only the distinct ones).

The product of its digits is 360000, while the sum is 42.

The spelling of 81555341532 in words is "eighty-one billion, five hundred fifty-five million, three hundred forty-one thousand, five hundred thirty-two".