81717464680 has 16 divisors (see below), whose sum is σ = 183864295620. Its totient is φ = 32686985856.

The previous prime is 81717464669. The next prime is 81717464683. The reversal of 81717464680 is 8646471718.

It can be written as a sum of positive squares in 2 ways, for example, as 72482639076 + 9234825604 = 269226^2 + 96098^2 .

It is not an unprimeable number, because it can be changed into a prime (81717464683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1021468269 + ... + 1021468348.

Almost surely, 2^81717464680 is an apocalyptic number.

It is an amenable number.

81717464680 is an abundant number, since it is smaller than the sum of its proper divisors (102146830940).

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

81717464680 is a wasteful number, since it uses less digits than its factorization.

81717464680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2042936628 (or 2042936624 counting only the distinct ones).

The product of its (nonzero) digits is 1806336, while the sum is 52.

The spelling of 81717464680 in words is "eighty-one billion, seven hundred seventeen million, four hundred sixty-four thousand, six hundred eighty".