1144161561 has 16 divisors (see below), whose sum is σ = 1562148864. Its totient is φ = 744560784.

The previous prime is 1144161559. The next prime is 1144161569. The reversal of 1144161561 is 1651614411.

It is not a de Polignac number, because 1144161561 - 2¹ = 1144161559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1144161569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43410 + ... + 64596.

It is an arithmetic number, because the mean of its divisors is an integer number (97634304).

Almost surely, 2^1144161561 is an apocalyptic number.

It is an amenable number.

1144161561 is a deficient number, since it is larger than the sum of its proper divisors (417987303).

1144161561 is a wasteful number, since it uses less digits than its factorization.

1144161561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21620.

The product of its digits is 2880, while the sum is 30.

The square root of 1144161561 is about 33825.4572918091. The cubic root of 1144161561 is about 1045.9135379740.

Adding to 1144161561 its reverse (1651614411), we get a palindrome (2795775972).

The spelling of 1144161561 in words is "one billion, one hundred forty-four million, one hundred sixty-one thousand, five hundred sixty-one".