81401796100 has 81 divisors (see below), whose sum is σ = 179019790047. Its totient is φ = 32128188480.

The previous prime is 81401796041. The next prime is 81401796103. The reversal of 81401796100 is 169710418.

The square root of 81401796100 is 285310.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 18653550084 + 62748246016 = 136578^2 + 250496^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81401796100.

It is not an unprimeable number, because it can be changed into a prime (81401796103) by changing a digit.

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 26 ways as a sum of consecutive naturals, for example, 293869162 + ... + 293869438.

Almost surely, 2^81401796100 is an apocalyptic number.

81401796100 is the 285310-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81401796100

81401796100 is an abundant number, since it is smaller than the sum of its proper divisors (97617993947).

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

81401796100 is a wasteful number, since it uses less digits than its factorization.

81401796100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 774 (or 387 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 37.

The spelling of 81401796100 in words is "eighty-one billion, four hundred one million, seven hundred ninety-six thousand, one hundred".