81116651151 has 64 divisors (see below), whose sum is σ = 130237977600. Its totient is φ = 49723632000.

The previous prime is 81116651117. The next prime is 81116651167. The reversal of 81116651151 is 15115661118.

It is a happy number.

81116651151 is a `hidden beast` number, since 81 + 1 + 1 + 66 + 511 + 5 + 1 = 666.

It is not a de Polignac number, because 81116651151 - 2⁹ = 81116650639 is a prime.

It is a super-2 number, since 2×81116651151² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81116651191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7985926 + ... + 7996076.

It is an arithmetic number, because the mean of its divisors is an integer number (2034968400).

Almost surely, 2^81116651151 is an apocalyptic number.

81116651151 is a deficient number, since it is larger than the sum of its proper divisors (49121326449).

81116651151 is a wasteful number, since it uses less digits than its factorization.

81116651151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10637 (or 10631 counting only the distinct ones).

The product of its digits is 7200, while the sum is 36.

The spelling of 81116651151 in words is "eighty-one billion, one hundred sixteen million, six hundred fifty-one thousand, one hundred fifty-one".