81946318 has 8 divisors (see below), whose sum is σ = 122964912. Its totient is φ = 40958016.

The previous prime is 81946313. The next prime is 81946327. The reversal of 81946318 is 81364918.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81946313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1246 + ... + 12862.

It is an arithmetic number, because the mean of its divisors is an integer number (15370614).

Almost surely, 2^81946318 is an apocalyptic number.

81946318 is a deficient number, since it is larger than the sum of its proper divisors (41018594).

81946318 is a wasteful number, since it uses less digits than its factorization.

81946318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15146.

The product of its digits is 41472, while the sum is 40.

The square root of 81946318 is about 9052.4205602701. The cubic root of 81946318 is about 434.3533228180.

The spelling of 81946318 in words is "eighty-one million, nine hundred forty-six thousand, three hundred eighteen".