780720444 has 120 divisors (see below), whose sum is σ = 2469852000. Its totient is φ = 209931264.

The previous prime is 780720443. The next prime is 780720449. The reversal of 780720444 is 444027087.

780720444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 780720399 and 780720408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (780720443) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 28432 + ... + 48680.

It is an arithmetic number, because the mean of its divisors is an integer number (20582100).

Almost surely, 2^780720444 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 780720444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1234926000).

780720444 is an abundant number, since it is smaller than the sum of its proper divisors (1689131556).

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

780720444 is a wasteful number, since it uses less digits than its factorization.

780720444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20289 (or 20278 counting only the distinct ones).

The product of its (nonzero) digits is 50176, while the sum is 36.

The square root of 780720444 is about 27941.3751272195. The cubic root of 780720444 is about 920.7997315193.

The spelling of 780720444 in words is "seven hundred eighty million, seven hundred twenty thousand, four hundred forty-four".