81946443 has 8 divisors (see below), whose sum is σ = 115689168. Its totient is φ = 51417344.

The previous prime is 81946441. The next prime is 81946517. The reversal of 81946443 is 34464918.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 81946443 - 2¹ = 81946441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81946441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 803346 + ... + 803447.

It is an arithmetic number, because the mean of its divisors is an integer number (14461146).

Almost surely, 2^81946443 is an apocalyptic number.

81946443 is a deficient number, since it is larger than the sum of its proper divisors (33742725).

81946443 is a wasteful number, since it uses less digits than its factorization.

81946443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1606813.

The product of its digits is 82944, while the sum is 39.

The square root of 81946443 is about 9052.4274644981. The cubic root of 81946443 is about 434.3535436704.

The spelling of 81946443 in words is "eighty-one million, nine hundred forty-six thousand, four hundred forty-three".