123121213345420 has 48 divisors (see below), whose sum is σ = 258689427087168. Its totient is φ = 49222800506880.

The previous prime is 123121213345253. The next prime is 123121213345423. The reversal of 123121213345420 is 24543312121321.

It is not an unprimeable number, because it can be changed into a prime (123121213345423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 313064305 + ... + 313457335.

It is an arithmetic number, because the mean of its divisors is an integer number (5389363064316).

Almost surely, 2^{123121213345420} is an apocalyptic number.

123121213345420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123121213345420 is an abundant number, since it is smaller than the sum of its proper divisors (135568213741748).

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

123121213345420 is a wasteful number, since it uses less digits than its factorization.

123121213345420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401170 (or 401168 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

Adding to 123121213345420 its reverse (24543312121321), we get a palindrome (147664525466741).

The spelling of 123121213345420 in words is "one hundred twenty-three trillion, one hundred twenty-one billion, two hundred thirteen million, three hundred forty-five thousand, four hundred twenty".