81742 has 8 divisors (see below), whose sum is σ = 128016. Its totient is φ = 39072.

The previous prime is 81737. The next prime is 81749. The reversal of 81742 is 24718.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 843 + ... + 934.

It is an arithmetic number, because the mean of its divisors is an integer number (16002).

2⁸¹⁷⁴² is an apocalyptic number.

81742 is a deficient number, since it is larger than the sum of its proper divisors (46274).

81742 is a wasteful number, since it uses less digits than its factorization.

81742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1802.

The product of its digits is 448, while the sum is 22.

The square root of 81742 is about 285.9055788193. The cubic root of 81742 is about 43.3992029131.

The spelling of 81742 in words is "eighty-one thousand, seven hundred forty-two".