123123013455540 has 192 divisors, whose sum is σ = 394933458898944. Its totient is φ = 28075336998912.

The previous prime is 123123013455529. The next prime is 123123013455553. The reversal of 123123013455540 is 45554310321321.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 373765987 + ... + 374095253.

It is an arithmetic number, because the mean of its divisors is an integer number (2056945098432).

Almost surely, 2^{123123013455540} is an apocalyptic number.

123123013455540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123123013455540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (197466729449472).

123123013455540 is an abundant number, since it is smaller than the sum of its proper divisors (271810445443404).

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

123123013455540 is a wasteful number, since it uses less digits than its factorization.

123123013455540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331406 (or 331404 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 39.

Adding to 123123013455540 its reverse (45554310321321), we get a palindrome (168677323776861).

The spelling of 123123013455540 in words is "one hundred twenty-three trillion, one hundred twenty-three billion, thirteen million, four hundred fifty-five thousand, five hundred forty".