81965713648508 has 24 divisors (see below), whose sum is σ = 144055833143040. Its totient is φ = 40806941482160.

The previous prime is 81965713648499. The next prime is 81965713648529. The reversal of 81965713648508 is 80584631756918.

It is a super-3 number, since 3×81965713648508³ (a number of 43 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4139903 + ... + 13456233.

It is an arithmetic number, because the mean of its divisors is an integer number (6002326380960).

Almost surely, 2^{81965713648508} is an apocalyptic number.

It is an amenable number.

81965713648508 is a deficient number, since it is larger than the sum of its proper divisors (62090119494532).

81965713648508 is a wasteful number, since it uses less digits than its factorization.

81965713648508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9325777 (or 9325775 counting only the distinct ones).

The product of its (nonzero) digits is 348364800, while the sum is 71.

The spelling of 81965713648508 in words is "eighty-one trillion, nine hundred sixty-five billion, seven hundred thirteen million, six hundred forty-eight thousand, five hundred eight".