81711752711 has 4 divisors (see below), whose sum is σ = 81714117024. Its totient is φ = 81709388400.

The previous prime is 81711752693. The next prime is 81711752741. The reversal of 81711752711 is 11725711718.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81711752711 - 2¹⁰ = 81711751687 is a prime.

It is a super-2 number, since 2×81711752711² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81711752741) 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, 1129535 + ... + 1199696.

It is an arithmetic number, because the mean of its divisors is an integer number (20428529256).

Almost surely, 2^81711752711 is an apocalyptic number.

81711752711 is a deficient number, since it is larger than the sum of its proper divisors (2364313).

81711752711 is a wasteful number, since it uses less digits than its factorization.

81711752711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2364312.

The product of its digits is 27440, while the sum is 41.

The spelling of 81711752711 in words is "eighty-one billion, seven hundred eleven million, seven hundred fifty-two thousand, seven hundred eleven".