81807064 has 16 divisors (see below), whose sum is σ = 154823400. Its totient is φ = 40520832.

The previous prime is 81807059. The next prime is 81807079. The reversal of 81807064 is 46070818.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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, 46929 + ... + 48640.

Almost surely, 2^81807064 is an apocalyptic number.

It is an amenable number.

81807064 is a deficient number, since it is larger than the sum of its proper divisors (73016336).

81807064 is a wasteful number, since it uses less digits than its factorization.

81807064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95682 (or 95678 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 34.

The square root of 81807064 is about 9044.7257559309. The cubic root of 81807064 is about 434.1071464874.

The spelling of 81807064 in words is "eighty-one million, eight hundred seven thousand, sixty-four".