81107100709 has 16 divisors (see below), whose sum is σ = 85968978048. Its totient is φ = 76365761472.

The previous prime is 81107100703. The next prime is 81107100727. The reversal of 81107100709 is 90700170118.

It is a cyclic number.

It is not a de Polignac number, because 81107100709 - 2⁵ = 81107100677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81107100703) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 281419 + ... + 491335.

It is an arithmetic number, because the mean of its divisors is an integer number (5373061128).

Almost surely, 2^81107100709 is an apocalyptic number.

It is an amenable number.

81107100709 is a deficient number, since it is larger than the sum of its proper divisors (4861877339).

81107100709 is a wasteful number, since it uses less digits than its factorization.

81107100709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210204.

The product of its (nonzero) digits is 3528, while the sum is 34.

The spelling of 81107100709 in words is "eighty-one billion, one hundred seven million, one hundred thousand, seven hundred nine".