121331440 has 120 divisors (see below), whose sum is σ = 306105408. Its totient is φ = 44689920.

The previous prime is 121331437. The next prime is 121331443. The reversal of 121331440 is 44133121.

It is an interprime number because it is at equal distance from previous prime (121331437) and next prime (121331443).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121331443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1989010 + ... + 1989070.

Almost surely, 2^121331440 is an apocalyptic number.

121331440 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 121331440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (153052704).

121331440 is an abundant number, since it is smaller than the sum of its proper divisors (184773968).

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

121331440 is a wasteful number, since it uses less digits than its factorization.

121331440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 121331440 is about 11015.0551519273. The cubic root of 121331440 is about 495.0599390057.

Adding to 121331440 its reverse (44133121), we get a palindrome (165464561).

It can be divided in two parts, 121331 and 440, that added together give a triangular number (121771 = T₄₉₃).

The spelling of 121331440 in words is "one hundred twenty-one million, three hundred thirty-one thousand, four hundred forty".