121408 has 28 divisors (see below), whose sum is σ = 276352. Its totient is φ = 51840.

The previous prime is 121403. The next prime is 121421. The reversal of 121408 is 804121.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (28).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 121391 and 121400.

It is not an unprimeable number, because it can be changed into a prime (121403) by changing a digit.

121408 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 313 + ... + 583.

2¹²¹⁴⁰⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138176).

121408 is an abundant number, since it is smaller than the sum of its proper divisors (154944).

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

121408 is an equidigital number, since it uses as much as digits as its factorization.

121408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290 (or 280 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 121408 is about 348.4365078461. The cubic root of 121408 is about 49.5164044531.

Adding to 121408 its reverse (804121), we get a palindrome (925529).

It can be divided in two parts, 121 and 408, that added together give a square (529 = 23²).

The spelling of 121408 in words is "one hundred twenty-one thousand, four hundred eight".