1061266561 has 2 divisors, whose sum is σ = 1061266562. Its totient is φ = 1061266560.

The previous prime is 1061266559. The next prime is 1061266639. The reversal of 1061266561 is 1656621601.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 947716225 + 113550336 = 30785^2 + 10656^2 .

It is a cyclic number.

It is not a de Polignac number, because 1061266561 - 2¹ = 1061266559 is a prime.

It is a super-2 number, since 2×1061266561² = 2252573426993533442, which contains 22 as substring.

Together with 1061266559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1061266511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 530633280 + 530633281.

It is an arithmetic number, because the mean of its divisors is an integer number (530633281).

Almost surely, 2^1061266561 is an apocalyptic number.

It is an amenable number.

1061266561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1061266561 is an equidigital number, since it uses as much as digits as its factorization.

1061266561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 1061266561 is about 32577.0864412396. The cubic root of 1061266561 is about 1020.0187619899.

The spelling of 1061266561 in words is "one billion, sixty-one million, two hundred sixty-six thousand, five hundred sixty-one".