81171767463 has 16 divisors (see below), whose sum is σ = 113051033856. Its totient is φ = 51708356480.

The previous prime is 81171767431. The next prime is 81171767473. The reversal of 81171767463 is 36476717118.

It is a cyclic number.

It is not a de Polignac number, because 81171767463 - 2⁵ = 81171767431 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81171767473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 538770 + ... + 672767.

It is an arithmetic number, because the mean of its divisors is an integer number (7065689616).

Almost surely, 2^81171767463 is an apocalyptic number.

81171767463 is a deficient number, since it is larger than the sum of its proper divisors (31879266393).

81171767463 is a wasteful number, since it uses less digits than its factorization.

81171767463 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1212534.

The product of its digits is 1185408, while the sum is 51.

The spelling of 81171767463 in words is "eighty-one billion, one hundred seventy-one million, seven hundred sixty-seven thousand, four hundred sixty-three".