20011012011961 has 2 divisors, whose sum is σ = 20011012011962. Its totient is φ = 20011012011960.

The previous prime is 20011012011959. The next prime is 20011012012073. The reversal of 20011012011961 is 16911021011002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11358113232400 + 8652898779561 = 3370180^2 + 2941581^2 .

It is a cyclic number.

It is not a de Polignac number, because 20011012011961 - 2¹ = 20011012011959 is a prime.

Together with 20011012011959, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20011012011941) 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, 10005506005980 + 10005506005981.

It is an arithmetic number, because the mean of its divisors is an integer number (10005506005981).

Almost surely, 2^{20011012011961} is an apocalyptic number.

It is an amenable number.

20011012011961 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011012011961 is an equidigital number, since it uses as much as digits as its factorization.

20011012011961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 25.

Adding to 20011012011961 its reverse (16911021011002), we get a palindrome (36922033022963).

The spelling of 20011012011961 in words is "twenty trillion, eleven billion, twelve million, eleven thousand, nine hundred sixty-one".