1123541989 has 2 divisors, whose sum is σ = 1123541990. Its totient is φ = 1123541988.

The previous prime is 1123541987. The next prime is 1123542001. The reversal of 1123541989 is 9891453211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 933791364 + 189750625 = 30558^2 + 13775^2 .

It is an emirp because it is prime and its reverse (9891453211) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1123541989 - 2¹ = 1123541987 is a prime.

It is a super-2 number, since 2×1123541989² = 2524693202092152242, which contains 22 as substring.

Together with 1123541987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1123541987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 561770994 + 561770995.

It is an arithmetic number, because the mean of its divisors is an integer number (561770995).

Almost surely, 2^1123541989 is an apocalyptic number.

It is an amenable number.

1123541989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1123541989 is an equidigital number, since it uses as much as digits as its factorization.

1123541989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 77760, while the sum is 43.

The square root of 1123541989 is about 33519.2778710998. The cubic root of 1123541989 is about 1039.5924157908.

The spelling of 1123541989 in words is "one billion, one hundred twenty-three million, five hundred forty-one thousand, nine hundred eighty-nine".