81738594107 has 4 divisors (see below), whose sum is σ = 81739172736. Its totient is φ = 81738015480.

The previous prime is 81738594101. The next prime is 81738594121. The reversal of 81738594107 is 70149583718.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 70149583718 = 2 ⋅35074791859.

It is a cyclic number.

It is not a de Polignac number, because 81738594107 - 2⁶ = 81738594043 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81738594101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78182 + ... + 411812.

It is an arithmetic number, because the mean of its divisors is an integer number (20434793184).

Almost surely, 2^81738594107 is an apocalyptic number.

81738594107 is a deficient number, since it is larger than the sum of its proper divisors (578629).

81738594107 is a wasteful number, since it uses less digits than its factorization.

81738594107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 578628.

The product of its (nonzero) digits is 1693440, while the sum is 53.

The spelling of 81738594107 in words is "eighty-one billion, seven hundred thirty-eight million, five hundred ninety-four thousand, one hundred seven".