123012555555 has 16 divisors (see below), whose sum is σ = 199592204544. Its totient is φ = 64682657760.

The previous prime is 123012555541. The next prime is 123012555559. The reversal of 123012555555 is 555555210321.

It is not a de Polignac number, because 123012555555 - 2⁴ = 123012555539 is a prime.

It is a super-2 number, since 2×123012555555² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (123012555559) 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 in 15 ways as a sum of consecutive naturals, for example, 57751309 + ... + 57753438.

It is an arithmetic number, because the mean of its divisors is an integer number (12474512784).

Almost surely, 2^123012555555 is an apocalyptic number.

123012555555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

123012555555 is a deficient number, since it is larger than the sum of its proper divisors (76579648989).

123012555555 is a wasteful number, since it uses less digits than its factorization.

123012555555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115504826.

The product of its (nonzero) digits is 187500, while the sum is 39.

Adding to 123012555555 its reverse (555555210321), we get a palindrome (678567765876).

The spelling of 123012555555 in words is "one hundred twenty-three billion, twelve million, five hundred fifty-five thousand, five hundred fifty-five".