121813440 has 112 divisors (see below), whose sum is σ = 442033152. Its totient is φ = 27841536.

The previous prime is 121813429. The next prime is 121813441. The reversal of 121813440 is 44318121.

It is a tau number, because it is divible by the number of its divisors (112).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 121813440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121813441) 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, 2344 + ... + 15783.

Almost surely, 2^121813440 is an apocalyptic number.

121813440 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 121813440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221016576).

121813440 is an abundant number, since it is smaller than the sum of its proper divisors (320219712).

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

121813440 is a wasteful number, since it uses less digits than its factorization.

121813440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18154 (or 18144 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 121813440 is about 11036.9126117769. The cubic root of 121813440 is about 495.7146294631.

The spelling of 121813440 in words is "one hundred twenty-one million, eight hundred thirteen thousand, four hundred forty".