1061566561 has 4 divisors (see below), whose sum is σ = 1158072624. Its totient is φ = 965060500.

The previous prime is 1061566553. The next prime is 1061566619. The reversal of 1061566561 is 1656651601.

1061566561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1656651601 = 11 ⋅150604691.

It is a cyclic number.

It is not a de Polignac number, because 1061566561 - 2³ = 1061566553 is a prime.

It is a super-2 number, since 2×1061566561² = 2253847126866733442, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1061566561.

It is not an unprimeable number, because it can be changed into a prime (1061563561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48253015 + ... + 48253036.

It is an arithmetic number, because the mean of its divisors is an integer number (289518156).

Almost surely, 2^1061566561 is an apocalyptic number.

1061566561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1061566561 is a deficient number, since it is larger than the sum of its proper divisors (96506063).

1061566561 is an equidigital number, since it uses as much as digits as its factorization.

1061566561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96506062.

The product of its (nonzero) digits is 32400, while the sum is 37.

The square root of 1061566561 is about 32581.6905792195. The cubic root of 1061566561 is about 1020.1148662771.

The spelling of 1061566561 in words is "one billion, sixty-one million, five hundred sixty-six thousand, five hundred sixty-one".