1116556561 has 2 divisors, whose sum is σ = 1116556562. Its totient is φ = 1116556560.

The previous prime is 1116556537. The next prime is 1116556577. The reversal of 1116556561 is 1656556111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1105961536 + 10595025 = 33256^2 + 3255^2 .

It is a cyclic number.

It is not a de Polignac number, because 1116556561 - 2¹³ = 1116548369 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1116556561.

It is not a weakly prime, because it can be changed into another prime (1116551561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 558278280 + 558278281.

It is an arithmetic number, because the mean of its divisors is an integer number (558278281).

Almost surely, 2^1116556561 is an apocalyptic number.

It is an amenable number.

1116556561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1116556561 is an equidigital number, since it uses as much as digits as its factorization.

1116556561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27000, while the sum is 37.

The square root of 1116556561 is about 33414.9152475358. The cubic root of 1116556561 is about 1037.4334398873.

The spelling of 1116556561 in words is "one billion, one hundred sixteen million, five hundred fifty-six thousand, five hundred sixty-one".