20011110100021 has 2 divisors, whose sum is σ = 20011110100022. Its totient is φ = 20011110100020.

The previous prime is 20011110099973. The next prime is 20011110100081. The reversal of 20011110100021 is 12000101111002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18405215416900 + 1605894683121 = 4290130^2 + 1267239^2 .

It is a cyclic number.

It is not a de Polignac number, because 20011110100021 - 2²³ = 20011101711413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20011110099980 and 20011110100007.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20011110100081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005555050010 + 10005555050011.

It is an arithmetic number, because the mean of its divisors is an integer number (10005555050011).

Almost surely, 2^{20011110100021} is an apocalyptic number.

It is an amenable number.

20011110100021 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011110100021 is an equidigital number, since it uses as much as digits as its factorization.

20011110100021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 20011110100021 its reverse (12000101111002), we get a palindrome (32011211211023).

The spelling of 20011110100021 in words is "twenty trillion, eleven billion, one hundred ten million, one hundred thousand, twenty-one".