81529473832 has 64 divisors (see below), whose sum is σ = 160399491840. Its totient is φ = 38809574400.

The previous prime is 81529473769. The next prime is 81529473833. The reversal of 81529473832 is 23837492518.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81529473832.

It is not an unprimeable number, because it can be changed into a prime (81529473833) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 5341732 + ... + 5356972.

It is an arithmetic number, because the mean of its divisors is an integer number (2506242060).

Almost surely, 2^81529473832 is an apocalyptic number.

81529473832 is a gapful number since it is divisible by the number (82) formed by its first and last digit.

It is an amenable number.

81529473832 is a deficient number, since it is larger than the sum of its proper divisors (78870018008).

81529473832 is a wasteful number, since it uses less digits than its factorization.

81529473832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15682 (or 15678 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 52.

The spelling of 81529473832 in words is "eighty-one billion, five hundred twenty-nine million, four hundred seventy-three thousand, eight hundred thirty-two".