81660934 has 8 divisors (see below), whose sum is σ = 124216848. Its totient is φ = 40255320.

The previous prime is 81660923. The next prime is 81660937. The reversal of 81660934 is 43906618.

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

It is a junction number, because it is equal to n+sod(n) for n = 81660893 and 81660902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81660937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 287397 + ... + 287680.

It is an arithmetic number, because the mean of its divisors is an integer number (15527106).

Almost surely, 2^81660934 is an apocalyptic number.

81660934 is a deficient number, since it is larger than the sum of its proper divisors (42555914).

81660934 is a wasteful number, since it uses less digits than its factorization.

81660934 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 575150.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 81660934 is about 9036.6439566910. The cubic root of 81660934 is about 433.8485140287.

The spelling of 81660934 in words is "eighty-one million, six hundred sixty thousand, nine hundred thirty-four".