81083646 has 32 divisors (see below), whose sum is σ = 205927680. Its totient is φ = 23166648.

The previous prime is 81083627. The next prime is 81083647. The reversal of 81083646 is 64638018.

It is a happy number.

81083646 is a `hidden beast` number, since 8 + 1 + 0 + 8 + 3 + 646 = 666.

It is a nialpdrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 81083646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81083647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 106876 + ... + 107631.

It is an arithmetic number, because the mean of its divisors is an integer number (6435240).

Almost surely, 2^81083646 is an apocalyptic number.

81083646 is an abundant number, since it is smaller than the sum of its proper divisors (124844034).

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

81083646 is a wasteful number, since it uses less digits than its factorization.

81083646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214525 (or 214519 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 81083646 is about 9004.6458009185. The cubic root of 81083646 is about 432.8237561601.

The spelling of 81083646 in words is "eighty-one million, eighty-three thousand, six hundred forty-six".