81835783 has 4 divisors (see below), whose sum is σ = 82586680. Its totient is φ = 81084888.

The previous prime is 81835781. The next prime is 81835799. The reversal of 81835783 is 38753818.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 38753818 = 2 ⋅19376909.

It is a cyclic number.

It is not a de Polignac number, because 81835783 - 2¹ = 81835781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81835781) 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 3 ways as a sum of consecutive naturals, for example, 375285 + ... + 375502.

It is an arithmetic number, because the mean of its divisors is an integer number (20646670).

Almost surely, 2^81835783 is an apocalyptic number.

81835783 is a deficient number, since it is larger than the sum of its proper divisors (750897).

81835783 is a wasteful number, since it uses less digits than its factorization.

81835783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 750896.

The product of its digits is 161280, while the sum is 43.

The square root of 81835783 is about 9046.3132269450. The cubic root of 81835783 is about 434.1579394300.

The spelling of 81835783 in words is "eighty-one million, eight hundred thirty-five thousand, seven hundred eighty-three".