81855735 has 32 divisors (see below), whose sum is σ = 147184128. Its totient is φ = 38544000.

The previous prime is 81855727. The next prime is 81855737. The reversal of 81855735 is 53755818.

It is a happy number.

It is not a de Polignac number, because 81855735 - 2³ = 81855727 is a prime.

It is a super-2 number, since 2×81855735² = 13400722704780450, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81855737) 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 31 ways as a sum of consecutive naturals, for example, 4641 + ... + 13610.

It is an arithmetic number, because the mean of its divisors is an integer number (4599504).

Almost surely, 2^81855735 is an apocalyptic number.

81855735 is a deficient number, since it is larger than the sum of its proper divisors (65328393).

81855735 is a wasteful number, since it uses less digits than its factorization.

81855735 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18295.

The product of its digits is 168000, while the sum is 42.

The square root of 81855735 is about 9047.4159294243. The cubic root of 81855735 is about 434.1932199028.

The spelling of 81855735 in words is "eighty-one million, eight hundred fifty-five thousand, seven hundred thirty-five".