81429432 has 64 divisors (see below), whose sum is σ = 235008000. Its totient is φ = 23030400.

The previous prime is 81429409. The next prime is 81429437. The reversal of 81429432 is 23492418.

It is a junction number, because it is equal to n+sod(n) for n = 81429393 and 81429402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81429437) 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 15 ways as a sum of consecutive naturals, for example, 14569 + ... + 19367.

It is an arithmetic number, because the mean of its divisors is an integer number (3672000).

Almost surely, 2^81429432 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 81429432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117504000).

81429432 is an abundant number, since it is smaller than the sum of its proper divisors (153578568).

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

81429432 is a wasteful number, since it uses less digits than its factorization.

81429432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4916 (or 4912 counting only the distinct ones).

The product of its digits is 13824, while the sum is 33.

The square root of 81429432 is about 9023.8257961909. The cubic root of 81429432 is about 433.4381511067.

The spelling of 81429432 in words is "eighty-one million, four hundred twenty-nine thousand, four hundred thirty-two".