1055111201561 has 2 divisors, whose sum is σ = 1055111201562. Its totient is φ = 1055111201560.

The previous prime is 1055111201513. The next prime is 1055111201567. The reversal of 1055111201561 is 1651021115501.

1055111201561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 685988123536 + 369123078025 = 828244^2 + 607555^2 .

It is a cyclic number.

It is not a de Polignac number, because 1055111201561 - 2¹⁸ = 1055110939417 is a prime.

It is a super-2 number, since 2×1055111201561² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1055111201567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 527555600780 + 527555600781.

It is an arithmetic number, because the mean of its divisors is an integer number (527555600781).

Almost surely, 2^{1055111201561} is an apocalyptic number.

It is an amenable number.

1055111201561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1055111201561 is an equidigital number, since it uses as much as digits as its factorization.

1055111201561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1500, while the sum is 29.

The spelling of 1055111201561 in words is "one trillion, fifty-five billion, one hundred eleven million, two hundred one thousand, five hundred sixty-one".