20001100109897 has 2 divisors, whose sum is σ = 20001100109898. Its totient is φ = 20001100109896.

The previous prime is 20001100109891. The next prime is 20001100109923. The reversal of 20001100109897 is 79890100110002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15098967576121 + 4902132533776 = 3885739^2 + 2214076^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001100109897 - 2¹⁸ = 20001099847753 is a prime.

It is a super-2 number, since 2×20001100109897² (a number of 27 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 20001100109897.

It is not a weakly prime, because it can be changed into another prime (20001100109891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000550054948 + 10000550054949.

It is an arithmetic number, because the mean of its divisors is an integer number (10000550054949).

Almost surely, 2^{20001100109897} is an apocalyptic number.

It is an amenable number.

20001100109897 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001100109897 is an equidigital number, since it uses as much as digits as its factorization.

20001100109897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 38.

Adding to 20001100109897 its reverse (79890100110002), we get a palindrome (99891200219899).

The spelling of 20001100109897 in words is "twenty trillion, one billion, one hundred million, one hundred nine thousand, eight hundred ninety-seven".