121620 has 24 divisors (see below), whose sum is σ = 340704. Its totient is φ = 32416.

The previous prime is 121609. The next prime is 121621. The reversal of 121620 is 26121.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 121596 and 121605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121621) by changing a digit.

121620 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 7 ways as a sum of consecutive naturals, for example, 954 + ... + 1073.

It is an arithmetic number, because the mean of its divisors is an integer number (14196).

2¹²¹⁶²⁰ is an apocalyptic number.

121620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121620 is an abundant number, since it is smaller than the sum of its proper divisors (219084).

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

121620 is a wasteful number, since it uses less digits than its factorization.

121620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2039 (or 2037 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 121620 is about 348.7405912709. The cubic root of 121620 is about 49.5452091818.

Adding to 121620 its reverse (26121), we get a palindrome (147741).

It can be divided in two parts, 121 and 620, that added together give a triangular number (741 = T₃₈).

The spelling of 121620 in words is "one hundred twenty-one thousand, six hundred twenty".