81729342 has 24 divisors (see below), whose sum is σ = 177321144. Its totient is φ = 27206064.

The previous prime is 81729313. The next prime is 81729343. The reversal of 81729342 is 24392718.

It is a junction number, because it is equal to n+sod(n) for n = 81729297 and 81729306.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81729343) 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 11 ways as a sum of consecutive naturals, for example, 12693 + ... + 18015.

It is an arithmetic number, because the mean of its divisors is an integer number (7388381).

Almost surely, 2^81729342 is an apocalyptic number.

81729342 is an abundant number, since it is smaller than the sum of its proper divisors (95591802).

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

81729342 is a wasteful number, since it uses less digits than its factorization.

81729342 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6184 (or 6181 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 81729342 is about 9040.4281978234. The cubic root of 81729342 is about 433.9696263084.

The spelling of 81729342 in words is "eighty-one million, seven hundred twenty-nine thousand, three hundred forty-two".