81413649765 has 48 divisors (see below), whose sum is σ = 169764816000. Its totient is φ = 35258841216.

The previous prime is 81413649739. The next prime is 81413649787. The reversal of 81413649765 is 56794631418.

81413649765 is a `hidden beast` number, since 8 + 14 + 136 + 497 + 6 + 5 = 666.

It is not a de Polignac number, because 81413649765 - 2⁷ = 81413649637 is a prime.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 6795490 + ... + 6807459.

It is an arithmetic number, because the mean of its divisors is an integer number (3536767000).

Almost surely, 2^81413649765 is an apocalyptic number.

It is an amenable number.

81413649765 is an abundant number, since it is smaller than the sum of its proper divisors (88351166235).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81413649765 is a wasteful number, since it uses less digits than its factorization.

81413649765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13602986 (or 13602983 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 54.

The spelling of 81413649765 in words is "eighty-one billion, four hundred thirteen million, six hundred forty-nine thousand, seven hundred sixty-five".