121321320120 has 384 divisors, whose sum is σ = 529403696640. Its totient is φ = 23270353920.

The previous prime is 121321320119. The next prime is 121321320137. The reversal of 121321320120 is 21023123121.

121321320120 is a `hidden beast` number, since 1 + 2 + 1 + 321 + 320 + 1 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 121321320093 and 121321320102.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 192027 + ... + 528693.

It is an arithmetic number, because the mean of its divisors is an integer number (1378655460).

Almost surely, 2^121321320120 is an apocalyptic number.

121321320120 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 121321320120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264701848320).

121321320120 is an abundant number, since it is smaller than the sum of its proper divisors (408082376520).

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

121321320120 is a wasteful number, since it uses less digits than its factorization.

121321320120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336715 (or 336708 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 121321320120 its reverse (21023123121), we get a palindrome (142344443241).

The spelling of 121321320120 in words is "one hundred twenty-one billion, three hundred twenty-one million, three hundred twenty thousand, one hundred twenty".