81967551164 has 12 divisors (see below), whose sum is σ = 143457252288. Its totient is φ = 40979764800.

The previous prime is 81967551163. The next prime is 81967551221. The reversal of 81967551164 is 46115576918.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81967551163) 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, 956477 + ... + 1038644.

It is an arithmetic number, because the mean of its divisors is an integer number (11954771024).

Almost surely, 2^81967551164 is an apocalyptic number.

It is an amenable number.

81967551164 is a deficient number, since it is larger than the sum of its proper divisors (61489701124).

81967551164 is a wasteful number, since it uses less digits than its factorization.

81967551164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2005396 (or 2005394 counting only the distinct ones).

The product of its digits is 1814400, while the sum is 53.

The spelling of 81967551164 in words is "eighty-one billion, nine hundred sixty-seven million, five hundred fifty-one thousand, one hundred sixty-four".