123400121020 has 24 divisors (see below), whose sum is σ = 282698459568. Its totient is φ = 44872771200.

The previous prime is 123400120939. The next prime is 123400121021. The reversal of 123400121020 is 20121004321.

It is a junction number, because it is equal to n+sod(n) for n = 123400120985 and 123400121003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123400121021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 280454601 + ... + 280455040.

It is an arithmetic number, because the mean of its divisors is an integer number (11779102482).

Almost surely, 2^123400121020 is an apocalyptic number.

123400121020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123400121020 is an abundant number, since it is smaller than the sum of its proper divisors (159298338548).

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

123400121020 is a wasteful number, since it uses less digits than its factorization.

123400121020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560909661 (or 560909659 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 123400121020 its reverse (20121004321), we get a palindrome (143521125341).

The spelling of 123400121020 in words is "one hundred twenty-three billion, four hundred million, one hundred twenty-one thousand, twenty".