81529332 has 12 divisors (see below), whose sum is σ = 190235136. Its totient is φ = 27176440.

The previous prime is 81529313. The next prime is 81529337. The reversal of 81529332 is 23392518.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 81529293 and 81529302.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81529337) 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 3 ways as a sum of consecutive naturals, for example, 3397044 + ... + 3397067.

It is an arithmetic number, because the mean of its divisors is an integer number (15852928).

Almost surely, 2^81529332 is an apocalyptic number.

It is an amenable number.

81529332 is an abundant number, since it is smaller than the sum of its proper divisors (108705804).

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

81529332 is a wasteful number, since it uses less digits than its factorization.

81529332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6794118 (or 6794116 counting only the distinct ones).

The product of its digits is 12960, while the sum is 33.

The square root of 81529332 is about 9029.3594457193. The cubic root of 81529332 is about 433.6153301883.

The spelling of 81529332 in words is "eighty-one million, five hundred twenty-nine thousand, three hundred thirty-two".