81942432 has 192 divisors, whose sum is σ = 260112384. Its totient is φ = 22256640.

The previous prime is 81942379. The next prime is 81942437. The reversal of 81942432 is 23424918.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 81942393 and 81942402.

It is not an unprimeable number, because it can be changed into a prime (81942437) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 645153 + ... + 645279.

It is an arithmetic number, because the mean of its divisors is an integer number (1354752).

Almost surely, 2^81942432 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 81942432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (130056192).

81942432 is an abundant number, since it is smaller than the sum of its proper divisors (178169952).

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

81942432 is a wasteful number, since it uses less digits than its factorization.

81942432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211 (or 203 counting only the distinct ones).

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

The square root of 81942432 is about 9052.2059190012. The cubic root of 81942432 is about 434.3464568447.

The spelling of 81942432 in words is "eighty-one million, nine hundred forty-two thousand, four hundred thirty-two".