20011211112161 has 2 divisors, whose sum is σ = 20011211112162. Its totient is φ = 20011211112160.

The previous prime is 20011211112149. The next prime is 20011211112197. The reversal of 20011211112161 is 16121111211002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19542765318400 + 468445793761 = 4420720^2 + 684431^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20011211112161 is a prime.

It is not a weakly prime, because it can be changed into another prime (20011219112161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005605556080 + 10005605556081.

It is an arithmetic number, because the mean of its divisors is an integer number (10005605556081).

Almost surely, 2^{20011211112161} is an apocalyptic number.

It is an amenable number.

20011211112161 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011211112161 is an equidigital number, since it uses as much as digits as its factorization.

20011211112161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 20.

Adding to 20011211112161 its reverse (16121111211002), we get a palindrome (36132322323163).

The spelling of 20011211112161 in words is "twenty trillion, eleven billion, two hundred eleven million, one hundred twelve thousand, one hundred sixty-one".