121320 has 48 divisors (see below), whose sum is σ = 395460. Its totient is φ = 32256.

The previous prime is 121313. The next prime is 121321. The reversal of 121320 is 23121.

121320 = T₁₀ + T₁₁ + ... + T₈₉.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 116964 + 4356 = 342^2 + 66^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (121321) by changing a digit.

121320 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 192 + ... + 528.

2¹²¹³²⁰ is an apocalyptic number.

121320 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 121320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (197730).

121320 is an abundant number, since it is smaller than the sum of its proper divisors (274140).

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

121320 is a wasteful number, since it uses less digits than its factorization.

121320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354 (or 347 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 121320 is about 348.3102065688. The cubic root of 121320 is about 49.5044379247.

Adding to 121320 its reverse (23121), we get a palindrome (144441).

It can be divided in two parts, 121 and 320, that added together give a square (441 = 21²).

The spelling of 121320 in words is "one hundred twenty-one thousand, three hundred twenty", and thus it is an iban number.