81748557694 has 8 divisors (see below), whose sum is σ = 122632761888. Its totient is φ = 40870970400.

The previous prime is 81748557689. The next prime is 81748557697. The reversal of 81748557694 is 49675584718.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81748557697) 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 3 ways as a sum of consecutive naturals, for example, 1623222 + ... + 1672825.

It is an arithmetic number, because the mean of its divisors is an integer number (15329095236).

Almost surely, 2^81748557694 is an apocalyptic number.

81748557694 is a deficient number, since it is larger than the sum of its proper divisors (40884204194).

81748557694 is a wasteful number, since it uses less digits than its factorization.

81748557694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3308450.

The product of its digits is 67737600, while the sum is 64.

The spelling of 81748557694 in words is "eighty-one billion, seven hundred forty-eight million, five hundred fifty-seven thousand, six hundred ninety-four".