81143512 has 16 divisors (see below), whose sum is σ = 152919360. Its totient is φ = 40365024.

The previous prime is 81143459. The next prime is 81143611. The reversal of 81143512 is 21534118.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24168 + ... + 27319.

It is an arithmetic number, because the mean of its divisors is an integer number (9557460).

Almost surely, 2^81143512 is an apocalyptic number.

It is an amenable number.

81143512 is a deficient number, since it is larger than the sum of its proper divisors (71775848).

81143512 is a wasteful number, since it uses less digits than its factorization.

81143512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51690 (or 51686 counting only the distinct ones).

The product of its digits is 960, while the sum is 25.

The square root of 81143512 is about 9007.9693605163. The cubic root of 81143512 is about 432.9302513407.

The spelling of 81143512 in words is "eighty-one million, one hundred forty-three thousand, five hundred twelve".