81938 has 8 divisors (see below), whose sum is σ = 125388. Its totient is φ = 40144.

The previous prime is 81937. The next prime is 81943. The reversal of 81938 is 83918.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 80089 + 1849 = 283^2 + 43^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 81938.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 81938.

It is not an unprimeable number, because it can be changed into a prime (81931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 281 + ... + 492.

2⁸¹⁹³⁸ is an apocalyptic number.

81938 is a deficient number, since it is larger than the sum of its proper divisors (43450).

81938 is a wasteful number, since it uses less digits than its factorization.

81938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828.

The product of its digits is 1728, while the sum is 29.

The square root of 81938 is about 286.2481440988. The cubic root of 81938 is about 43.4338625907.

The spelling of 81938 in words is "eighty-one thousand, nine hundred thirty-eight".