81384806610 has 48 divisors (see below), whose sum is σ = 216102646656. Its totient is φ = 21240856224.

The previous prime is 81384806609. The next prime is 81384806681. The reversal of 81384806610 is 1660848318.

It is a happy number.

81384806610 is a `hidden beast` number, since 81 + 38 + 480 + 6 + 61 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 23 ways as a sum of consecutive naturals, for example, 9615724 + ... + 9624183.

It is an arithmetic number, because the mean of its divisors is an integer number (4502138472).

Almost surely, 2^81384806610 is an apocalyptic number.

81384806610 is an abundant number, since it is smaller than the sum of its proper divisors (134717840046).

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

81384806610 is a wasteful number, since it uses less digits than its factorization.

81384806610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19239967 (or 19239964 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The spelling of 81384806610 in words is "eighty-one billion, three hundred eighty-four million, eight hundred six thousand, six hundred ten".