121645440 has 288 divisors, whose sum is σ = 489771360. Its totient is φ = 27740160.

The previous prime is 121645439. The next prime is 121645463. The reversal of 121645440 is 44546121.

121645440 is a `hidden beast` number, since 1 + 216 + 4 + 5 + 440 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×121645440² = 29595226145587200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 282025 + ... + 282455.

It is an arithmetic number, because the mean of its divisors is an integer number (1700595).

Almost surely, 2^121645440 is an apocalyptic number.

121645440 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 121645440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244885680).

121645440 is an abundant number, since it is smaller than the sum of its proper divisors (368125920).

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

121645440 is a wasteful number, since it uses less digits than its factorization.

121645440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470 (or 448 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 121645440 is about 11029.2991617781. The cubic root of 121645440 is about 495.4866349917.

It can be divided in two parts, 1216 and 45440, that added together give a 6-th power (46656 = 6⁶).

The spelling of 121645440 in words is "one hundred twenty-one million, six hundred forty-five thousand, four hundred forty".