121605408 has 96 divisors (see below), whose sum is σ = 358585920. Its totient is φ = 40089600.

The previous prime is 121605397. The next prime is 121605409. The reversal of 121605408 is 804506121.

121605408 is a `hidden beast` number, since 12 + 1 + 605 + 40 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (121605409) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83083 + ... + 84533.

It is an arithmetic number, because the mean of its divisors is an integer number (3735270).

Almost surely, 2^121605408 is an apocalyptic number.

121605408 is a gapful number since it is divisible by the number (18) 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 121605408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179292960).

121605408 is an abundant number, since it is smaller than the sum of its proper divisors (236980512).

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

121605408 is a wasteful number, since it uses less digits than its factorization.

121605408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1567 (or 1553 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 121605408 is about 11027.4842099184. The cubic root of 121605408 is about 495.4322762005.

The spelling of 121605408 in words is "one hundred twenty-one million, six hundred five thousand, four hundred eight".