81943113 has 8 divisors (see below), whose sum is σ = 124865728. Its totient is φ = 46824624.

The previous prime is 81943097. The next prime is 81943139. The reversal of 81943113 is 31134918.

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

It is not a de Polignac number, because 81943113 - 2⁴ = 81943097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81944113) 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, 1951006 + ... + 1951047.

It is an arithmetic number, because the mean of its divisors is an integer number (15608216).

Almost surely, 2^81943113 is an apocalyptic number.

It is an amenable number.

81943113 is a deficient number, since it is larger than the sum of its proper divisors (42922615).

81943113 is a wasteful number, since it uses less digits than its factorization.

81943113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3902063.

The product of its digits is 2592, while the sum is 30.

The square root of 81943113 is about 9052.2435340638. The cubic root of 81943113 is about 434.3476600842.

The spelling of 81943113 in words is "eighty-one million, nine hundred forty-three thousand, one hundred thirteen".