2111561655611 has 2 divisors, whose sum is σ = 2111561655612. Its totient is φ = 2111561655610.

The previous prime is 2111561655589. The next prime is 2111561655617. The reversal of 2111561655611 is 1165561651112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2111561655611 - 2¹⁴ = 2111561639227 is a prime.

It is not a weakly prime, because it can be changed into another prime (2111561655617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1055780827805 + 1055780827806.

It is an arithmetic number, because the mean of its divisors is an integer number (1055780827806).

Almost surely, 2^{2111561655611} is an apocalyptic number.

2111561655611 is a deficient number, since it is larger than the sum of its proper divisors (1).

2111561655611 is an equidigital number, since it uses as much as digits as its factorization.

2111561655611 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54000, while the sum is 41.

The spelling of 2111561655611 in words is "two trillion, one hundred eleven billion, five hundred sixty-one million, six hundred fifty-five thousand, six hundred eleven".