123256605620 has 24 divisors (see below), whose sum is σ = 267764351400. Its totient is φ = 47602550912.

The previous prime is 123256605613. The next prime is 123256605629. The reversal of 123256605620 is 26506652321.

It can be written as a sum of positive squares in 4 ways, for example, as 40886457616 + 82370148004 = 202204^2 + 287002^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123256605629) 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 in 7 ways as a sum of consecutive naturals, for example, 106255115 + ... + 106256274.

It is an arithmetic number, because the mean of its divisors is an integer number (11156847975).

Almost surely, 2^123256605620 is an apocalyptic number.

123256605620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123256605620 is an abundant number, since it is smaller than the sum of its proper divisors (144507745780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

123256605620 is a wasteful number, since it uses less digits than its factorization.

123256605620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212511427 (or 212511425 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 38.

The spelling of 123256605620 in words is "one hundred twenty-three billion, two hundred fifty-six million, six hundred five thousand, six hundred twenty".