20011333261 has 2 divisors, whose sum is σ = 20011333262. Its totient is φ = 20011333260.

The previous prime is 20011333219. The next prime is 20011333271. The reversal of 20011333261 is 16233311002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16950477636 + 3060855625 = 130194^2 + 55325^2 .

It is a cyclic number.

It is not a de Polignac number, because 20011333261 - 2⁹ = 20011332749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20011333271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005666630 + 10005666631.

It is an arithmetic number, because the mean of its divisors is an integer number (10005666631).

Almost surely, 2^20011333261 is an apocalyptic number.

It is an amenable number.

20011333261 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011333261 is an equidigital number, since it uses as much as digits as its factorization.

20011333261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 22.

Adding to 20011333261 its reverse (16233311002), we get a palindrome (36244644263).

The spelling of 20011333261 in words is "twenty billion, eleven million, three hundred thirty-three thousand, two hundred sixty-one".