100641205981 has 2 divisors, whose sum is σ = 100641205982. Its totient is φ = 100641205980.

The previous prime is 100641205957. The next prime is 100641206069. The reversal of 100641205981 is 189502146001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89853060025 + 10788145956 = 299755^2 + 103866^2 .

It is a cyclic number.

It is not a de Polignac number, because 100641205981 - 2³¹ = 98493722333 is a prime.

It is a super-2 number, since 2×100641205981² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 100641205981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100641205901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50320602990 + 50320602991.

It is an arithmetic number, because the mean of its divisors is an integer number (50320602991).

Almost surely, 2^100641205981 is an apocalyptic number.

It is an amenable number.

100641205981 is a deficient number, since it is larger than the sum of its proper divisors (1).

100641205981 is an equidigital number, since it uses as much as digits as its factorization.

100641205981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 37.

The spelling of 100641205981 in words is "one hundred billion, six hundred forty-one million, two hundred five thousand, nine hundred eighty-one".