120721440 has 384 divisors, whose sum is σ = 479969280. Its totient is φ = 24883200.

The previous prime is 120721429. The next prime is 120721441. The reversal of 120721440 is 44127021.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (120721441) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1979010 + ... + 1979070.

It is an arithmetic number, because the mean of its divisors is an integer number (1249920).

Almost surely, 2^120721440 is an apocalyptic number.

120721440 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 120721440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (239984640).

120721440 is an abundant number, since it is smaller than the sum of its proper divisors (359247840).

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

120721440 is a wasteful number, since it uses less digits than its factorization.

120721440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136 (or 128 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 120721440 is about 10987.3308860706. The cubic root of 120721440 is about 494.2288983858.

Adding to 120721440 its reverse (44127021), we get a palindrome (164848461).

The spelling of 120721440 in words is "one hundred twenty million, seven hundred twenty-one thousand, four hundred forty".