20011011111001 has 2 divisors, whose sum is σ = 20011011111002. Its totient is φ = 20011011111000.

The previous prime is 20011011110983. The next prime is 20011011111023. The reversal of 20011011111001 is 10011111011002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19961594265600 + 49416845401 = 4467840^2 + 222299^2 .

It is a cyclic number.

It is not a de Polignac number, because 20011011111001 - 2¹³ = 20011011102809 is a prime.

It is not a weakly prime, because it can be changed into another prime (20011011111031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005505555500 + 10005505555501.

It is an arithmetic number, because the mean of its divisors is an integer number (10005505555501).

Almost surely, 2^{20011011111001} is an apocalyptic number.

It is an amenable number.

20011011111001 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011011111001 is an equidigital number, since it uses as much as digits as its factorization.

20011011111001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2, while the sum is 10.

Adding to 20011011111001 its reverse (10011111011002), we get a palindrome (30022122122003).

Subtracting from 20011011111001 its reverse (10011111011002), we obtain a palindrome (9999900099999).

The spelling of 20011011111001 in words is "twenty trillion, eleven billion, eleven million, one hundred eleven thousand, one".