2111211220081 has 2 divisors, whose sum is σ = 2111211220082. Its totient is φ = 2111211220080.

The previous prime is 2111211219989. The next prime is 2111211220091. The reversal of 2111211220081 is 1800221121112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1077684829456 + 1033526390625 = 1038116^2 + 1016625^2 .

It is a cyclic number.

It is not a de Polignac number, because 2111211220081 - 2⁹ = 2111211219569 is a prime.

It is a super-2 number, since 2×2111211220081² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2111211220091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1055605610040 + 1055605610041.

It is an arithmetic number, because the mean of its divisors is an integer number (1055605610041).

Almost surely, 2^{2111211220081} is an apocalyptic number.

It is an amenable number.

2111211220081 is a deficient number, since it is larger than the sum of its proper divisors (1).

2111211220081 is an equidigital number, since it uses as much as digits as its factorization.

2111211220081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 22.

Adding to 2111211220081 its reverse (1800221121112), we get a palindrome (3911432341193).

The spelling of 2111211220081 in words is "two trillion, one hundred eleven billion, two hundred eleven million, two hundred twenty thousand, eighty-one".