123221120421 has 16 divisors (see below), whose sum is σ = 192345164928. Its totient is φ = 68694700800.

The previous prime is 123221120389. The next prime is 123221120423. The reversal of 123221120421 is 124021122321.

It is a happy number.

It is not a de Polignac number, because 123221120421 - 2⁵ = 123221120389 is a prime.

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 (123221120423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71556120 + ... + 71557841.

It is an arithmetic number, because the mean of its divisors is an integer number (12021572808).

Almost surely, 2^123221120421 is an apocalyptic number.

It is an amenable number.

123221120421 is a deficient number, since it is larger than the sum of its proper divisors (69124044507).

123221120421 is a wasteful number, since it uses less digits than its factorization.

123221120421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143114012.

The product of its (nonzero) digits is 384, while the sum is 21.

Adding to 123221120421 its reverse (124021122321), we get a palindrome (247242242742).

The spelling of 123221120421 in words is "one hundred twenty-three billion, two hundred twenty-one million, one hundred twenty thousand, four hundred twenty-one".