81524777168 has 20 divisors (see below), whose sum is σ = 158097494208. Its totient is φ = 40725423840.

The previous prime is 81524777161. The next prime is 81524777171. The reversal of 81524777168 is 86177742518.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81524777161) 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, 2292098 + ... + 2327393.

Almost surely, 2^81524777168 is an apocalyptic number.

It is an amenable number.

81524777168 is a deficient number, since it is larger than the sum of its proper divisors (76572717040).

81524777168 is a wasteful number, since it uses less digits than its factorization.

81524777168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4620602 (or 4620596 counting only the distinct ones).

The product of its digits is 5268480, while the sum is 56.

The spelling of 81524777168 in words is "eighty-one billion, five hundred twenty-four million, seven hundred seventy-seven thousand, one hundred sixty-eight".