211220021210111 has 2 divisors, whose sum is σ = 211220021210112. Its totient is φ = 211220021210110.

The previous prime is 211220021209927. The next prime is 211220021210131. The reversal of 211220021210111 is 111012120022112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 211220021210111 - 2²² = 211220017015807 is a prime.

It is a super-2 number, since 2×211220021210111² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 211220021210111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211220021210131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105610010605055 + 105610010605056.

It is an arithmetic number, because the mean of its divisors is an integer number (105610010605056).

Almost surely, 2^{211220021210111} is an apocalyptic number.

211220021210111 is a deficient number, since it is larger than the sum of its proper divisors (1).

211220021210111 is an equidigital number, since it uses as much as digits as its factorization.

211220021210111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 211220021210111 its reverse (111012120022112), we get a palindrome (322232141232223).

The spelling of 211220021210111 in words is "two hundred eleven trillion, two hundred twenty billion, twenty-one million, two hundred ten thousand, one hundred eleven".