123121132320420 has 432 divisors, whose sum is σ = 428261275954512. Its totient is φ = 28519518044160.

The previous prime is 123121132320353. The next prime is 123121132320449. The reversal of 123121132320420 is 24023231121321.

123121132320420 is a `hidden beast` number, since 1 + 2 + 3 + 1 + 2 + 1 + 1 + 3 + 232 + 0 + 420 = 666.

It can be written as a sum of positive squares in 24 ways, for example, as 120062467119204 + 3058665201216 = 10957302^2 + 1748904^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 4220364954 + ... + 4220394126.

It is an arithmetic number, because the mean of its divisors is an integer number (991345546191).

Almost surely, 2^{123121132320420} is an apocalyptic number.

123121132320420 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 123121132320420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (214130637977256).

123121132320420 is an abundant number, since it is smaller than the sum of its proper divisors (305140143634092).

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

123121132320420 is a wasteful number, since it uses less digits than its factorization.

123121132320420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37392 (or 37374 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

Adding to 123121132320420 its reverse (24023231121321), we get a palindrome (147144363441741).

The spelling of 123121132320420 in words is "one hundred twenty-three trillion, one hundred twenty-one billion, one hundred thirty-two million, three hundred twenty thousand, four hundred twenty".