211220120011111 has 2 divisors, whose sum is σ = 211220120011112. Its totient is φ = 211220120011110.

The previous prime is 211220120011091. The next prime is 211220120011171. The reversal of 211220120011111 is 111110021022112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 211220120011111 - 2⁵ = 211220120011079 is a prime.

It is a super-2 number, since 2×211220120011111² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211220120011171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105610060005555 + 105610060005556.

It is an arithmetic number, because the mean of its divisors is an integer number (105610060005556).

Almost surely, 2^{211220120011111} is an apocalyptic number.

211220120011111 is a deficient number, since it is larger than the sum of its proper divisors (1).

211220120011111 is an equidigital number, since it uses as much as digits as its factorization.

211220120011111 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 16.

Adding to 211220120011111 its reverse (111110021022112), we get a palindrome (322330141033223).

The spelling of 211220120011111 in words is "two hundred eleven trillion, two hundred twenty billion, one hundred twenty million, eleven thousand, one hundred eleven".