81743625688 has 16 divisors (see below), whose sum is σ = 157007574360. Its totient is φ = 39874939200.

The previous prime is 81743625553. The next prime is 81743625701. The reversal of 81743625688 is 88652634718.

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 (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124608858 + ... + 124609513.

Almost surely, 2^81743625688 is an apocalyptic number.

It is an amenable number.

81743625688 is a deficient number, since it is larger than the sum of its proper divisors (75263948672).

81743625688 is a wasteful number, since it uses less digits than its factorization.

81743625688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249218418 (or 249218414 counting only the distinct ones).

The product of its digits is 15482880, while the sum is 58.

The spelling of 81743625688 in words is "eighty-one billion, seven hundred forty-three million, six hundred twenty-five thousand, six hundred eighty-eight".