81776960008 has 8 divisors (see below), whose sum is σ = 153331800030. Its totient is φ = 40888480000.

The previous prime is 81776959991. The next prime is 81776960063. The reversal of 81776960008 is 80006967718.

It can be written as a sum of positive squares in only one way, i.e., 81749102724 + 27857284 = 285918^2 + 5278^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5111059993 + ... + 5111060008.

Almost surely, 2^81776960008 is an apocalyptic number.

It is an amenable number.

81776960008 is a deficient number, since it is larger than the sum of its proper divisors (71554840022).

81776960008 is a wasteful number, since it uses less digits than its factorization.

81776960008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10222120007 (or 10222120003 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 52.

The spelling of 81776960008 in words is "eighty-one billion, seven hundred seventy-six million, nine hundred sixty thousand, eight".