1123456729 has 2 divisors, whose sum is σ = 1123456730. Its totient is φ = 1123456728.

The previous prime is 1123456727. The next prime is 1123456751. The reversal of 1123456729 is 9276543211.

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., 1095610000 + 27846729 = 33100^2 + 5277^2 .

It is a cyclic number.

It is not a de Polignac number, because 1123456729 - 2¹ = 1123456727 is a prime.

It is a super-3 number, since 3×1123456729³ (a number of 28 digits) contains 333 as substring.

Together with 1123456727, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1123456691 and 1123456700.

It is not a weakly prime, because it can be changed into another prime (1123456727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 561728364 + 561728365.

It is an arithmetic number, because the mean of its divisors is an integer number (561728365).

Almost surely, 2^1123456729 is an apocalyptic number.

It is an amenable number.

1123456729 is a deficient number, since it is larger than the sum of its proper divisors (1).

1123456729 is an equidigital number, since it uses as much as digits as its factorization.

1123456729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 40.

The square root of 1123456729 is about 33518.0060415294. The cubic root of 1123456729 is about 1039.5661186305.

The spelling of 1123456729 in words is "one billion, one hundred twenty-three million, four hundred fifty-six thousand, seven hundred twenty-nine".