81145866 has 8 divisors (see below), whose sum is σ = 162291744. Its totient is φ = 27048620.

The previous prime is 81145853. The next prime is 81145871. The reversal of 81145866 is 66854118.

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

81145866 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6762150 + ... + 6762161.

It is an arithmetic number, because the mean of its divisors is an integer number (20286468).

Almost surely, 2^81145866 is an apocalyptic number.

81145866 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81145866 is a wasteful number, since it uses less digits than its factorization.

81145866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13524316.

The product of its digits is 46080, while the sum is 39.

The square root of 81145866 is about 9008.1000216472. The cubic root of 81145866 is about 432.9344377833.

The spelling of 81145866 in words is "eighty-one million, one hundred forty-five thousand, eight hundred sixty-six".