1055611561 has 4 divisors (see below), whose sum is σ = 1055678932. Its totient is φ = 1055544192.

The previous prime is 1055611541. The next prime is 1055611621. The reversal of 1055611561 is 1651165501.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1651165501 = 1489 ⋅1108909.

It can be written as a sum of positive squares in 2 ways, for example, as 1002102336 + 53509225 = 31656^2 + 7315^2 .

It is a cyclic number.

It is not a de Polignac number, because 1055611561 - 2⁷ = 1055611433 is a prime.

It is a super-2 number, since 2×1055611561² = 2228631535433713442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1055611511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3505 + ... + 46081.

It is an arithmetic number, because the mean of its divisors is an integer number (263919733).

Almost surely, 2^1055611561 is an apocalyptic number.

It is an amenable number.

1055611561 is a deficient number, since it is larger than the sum of its proper divisors (67371).

1055611561 is an equidigital number, since it uses as much as digits as its factorization.

1055611561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67370.

The product of its (nonzero) digits is 4500, while the sum is 31.

The square root of 1055611561 is about 32490.1763768681. The cubic root of 1055611561 is about 1018.2037979589.

The spelling of 1055611561 in words is "one billion, fifty-five million, six hundred eleven thousand, five hundred sixty-one".