1161565553 has 2 divisors, whose sum is σ = 1161565554. Its totient is φ = 1161565552.

The previous prime is 1161565541. The next prime is 1161565633. The reversal of 1161565553 is 3555651611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1038643984 + 122921569 = 32228^2 + 11087^2 .

It is a cyclic number.

It is not a de Polignac number, because 1161565553 - 2¹⁰ = 1161564529 is a prime.

It is not a weakly prime, because it can be changed into another prime (1161564553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 580782776 + 580782777.

It is an arithmetic number, because the mean of its divisors is an integer number (580782777).

Almost surely, 2^1161565553 is an apocalyptic number.

It is an amenable number.

1161565553 is a deficient number, since it is larger than the sum of its proper divisors (1).

1161565553 is an equidigital number, since it uses as much as digits as its factorization.

1161565553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 67500, while the sum is 38.

The square root of 1161565553 is about 34081.7480919040. The cubic root of 1161565553 is about 1051.1900499547.

The spelling of 1161565553 in words is "one billion, one hundred sixty-one million, five hundred sixty-five thousand, five hundred fifty-three".