81708664741 has 12 divisors (see below), whose sum is σ = 94538953600. Its totient is φ = 70371096840.

The previous prime is 81708664699. The next prime is 81708664753. The reversal of 81708664741 is 14746680718.

It is not a de Polignac number, because 81708664741 - 2⁹ = 81708664229 is a prime.

It is a hoax number, since the sum of its digits (52) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81708664771) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17768181 + ... + 17772778.

Almost surely, 2^81708664741 is an apocalyptic number.

It is an amenable number.

81708664741 is a deficient number, since it is larger than the sum of its proper divisors (12830288859).

81708664741 is a wasteful number, since it uses less digits than its factorization.

81708664741 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35541000 (or 35540989 counting only the distinct ones).

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

The spelling of 81708664741 in words is "eighty-one billion, seven hundred eight million, six hundred sixty-four thousand, seven hundred forty-one".