81787109375 has 28 divisors (see below), whose sum is σ = 103759765608. Its totient is φ = 64453125000.

The previous prime is 81787109329. The next prime is 81787109389. The reversal of 81787109375 is 57390178718.

It is a happy number.

It is a trimorphic number since its cube, 547084709978662431240081787109375, ends in 81787109375.

It is not a de Polignac number, because 81787109375 - 2⁶ = 81787109311 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81787109375.

It is a congruent number.

It is an unprimeable number.

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 27 ways as a sum of consecutive naturals, for example, 1220703092 + ... + 1220703158.

Almost surely, 2^81787109375 is an apocalyptic number.

81787109375 is a deficient number, since it is larger than the sum of its proper divisors (21972656233).

81787109375 is an frugal number, since it uses more digits than its factorization.

81787109375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132 (or 72 counting only the distinct ones).

The product of its (nonzero) digits is 2963520, while the sum is 56.

The spelling of 81787109375 in words is "eighty-one billion, seven hundred eighty-seven million, one hundred nine thousand, three hundred seventy-five".