81079810196 has 108 divisors (see below), whose sum is σ = 187682058900. Its totient is φ = 30499983360.

The previous prime is 81079810187. The next prime is 81079810199. The reversal of 81079810196 is 69101897018.

It can be written as a sum of positive squares in 2 ways, for example, as 32243230096 + 48836580100 = 179564^2 + 220990^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81079810199) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 628820 + ... + 746708.

Almost surely, 2^81079810196 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81079810196, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93841029450).

81079810196 is an abundant number, since it is smaller than the sum of its proper divisors (106602248704).

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

81079810196 is a wasteful number, since it uses less digits than its factorization.

81079810196 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117958 (or 117938 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 50.

The spelling of 81079810196 in words is "eighty-one billion, seventy-nine million, eight hundred ten thousand, one hundred ninety-six".