123456679009 has 2 divisors, whose sum is σ = 123456679010. Its totient is φ = 123456679008.

The previous prime is 123456679001. The next prime is 123456679019. The reversal of 123456679009 is 900976654321.

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., 119218278400 + 4238400609 = 345280^2 + 65103^2 .

It is an emirp because it is prime and its reverse (900976654321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 123456679009 - 2³ = 123456679001 is a prime.

It is a super-2 number, since 2×123456679009² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (123456679001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61728339504 + 61728339505.

It is an arithmetic number, because the mean of its divisors is an integer number (61728339505).

Almost surely, 2^123456679009 is an apocalyptic number.

It is an amenable number.

123456679009 is a deficient number, since it is larger than the sum of its proper divisors (1).

123456679009 is an equidigital number, since it uses as much as digits as its factorization.

123456679009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2449440, while the sum is 52.

The spelling of 123456679009 in words is "one hundred twenty-three billion, four hundred fifty-six million, six hundred seventy-nine thousand, nine".