123121121340 has 96 divisors (see below), whose sum is σ = 394033618944. Its totient is φ = 28138682880.

The previous prime is 123121121329. The next prime is 123121121341. The reversal of 123121121340 is 43121121321.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123121121341) 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 31 ways as a sum of consecutive naturals, for example, 7060312 + ... + 7077728.

It is an arithmetic number, because the mean of its divisors is an integer number (4104516864).

Almost surely, 2^123121121340 is an apocalyptic number.

123121121340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123121121340 is an abundant number, since it is smaller than the sum of its proper divisors (270912497604).

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

123121121340 is a wasteful number, since it uses less digits than its factorization.

123121121340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34267 (or 34265 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 21.

Adding to 123121121340 its reverse (43121121321), we get a palindrome (166242242661).

The spelling of 123121121340 in words is "one hundred twenty-three billion, one hundred twenty-one million, one hundred twenty-one thousand, three hundred forty".