81335838 has 16 divisors (see below), whose sum is σ = 162775296. Its totient is φ = 27094680.

The previous prime is 81335831. The next prime is 81335851. The reversal of 81335838 is 83853318.

It is a junction number, because it is equal to n+sod(n) for n = 81335796 and 81335805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81335831) 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 7 ways as a sum of consecutive naturals, for example, 9093 + ... + 15663.

It is an arithmetic number, because the mean of its divisors is an integer number (10173456).

Almost surely, 2^81335838 is an apocalyptic number.

81335838 is an abundant number, since it is smaller than the sum of its proper divisors (81439458).

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

81335838 is a wasteful number, since it uses less digits than its factorization.

81335838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8639.

The product of its digits is 69120, while the sum is 39.

The square root of 81335838 is about 9018.6383672925. The cubic root of 81335838 is about 433.2720245939.

The spelling of 81335838 in words is "eighty-one million, three hundred thirty-five thousand, eight hundred thirty-eight".